Where this unit fits in Prior learningThis unit builds on:unit 8A Food and digestion, which needs to have been covered first. The unit relates to work on foods andfuels in unit 7I Energy resources and to work on oxygen and burning in unit 7F Simple chemical reactions.
The concepts in this unit are: transport of the materials needed by cells for respiration, release of energy by plant and animal cells,respiration is similar in all cells.
This unit leads onto:the section on breathing and smoking in unit 9B Fit and healthy. The unit lays the foundation for workon the composition of the blood, the structure of blood cells and the circulatory system at key stage 4.
To make good progress, pupils startingthis unit need to understand … • Energy transfer as introduced in 7I
Energy resources. Energy should bedistinguished from ‘stuff’ (the food asenergy resource or fuel).
• Oxygen, burning and word equations as introduced in 7F Simple chemicalreactions.
Framework yearly teaching objectives – Cells• Explain that cells obtain energy through respiration, which often requires oxygen (aerobic respiration); use this to explain why tissues need a good
blood supply; identify similarities in aerobic respiration in animals and plants.
Expectations from the QCA Scheme of Work At the end of this unit …
… most pupils will … … some pupils will not have madeso much progress and will …
… some pupils will have progressedfurther and will …
in terms of scientific enquiry NC Programme of Study Sc1 2c, d, e, f, g, h, i, j, k, l
• describe an earlier model of circulation indicating how it doesnot match present-day evidence
• explain why control experiments and sample size are importantwhen investigating living organisms
• make appropriate observations, recording them accurately andidentifying patterns in data obtained.
• recognise that ideas aboutcirculation have changed
• with help, identify variablesrelevant to a question
• make observations and recognisepatterns in data.
• describe and explain some of theevidence leading to present-day ideasabout how and why blood circulates.
in terms of life processes and living things NC Programme of Study Sc2 2c, d, l, j, k, l, 3e; Sc3 1b; Sc4 5a
• describe the role of blood in transporting carbon dioxide from,and oxygen to, the lungs and explain why tissues need a goodblood supply
• describe aerobic respiration as a reaction with oxygen • describe some effects of an inadequate oxygen supply • describe and explain differences between inhaled and exhaled air
and identify similarities in aerobic respiration in plants andanimals.
• recognise that oxygen is requiredfor aerobic respiration and thatoxygen and glucose are transportedin the blood
• describe differences betweeninhaled and exhaled air.
• represent the process of aerobicrespiration as a word and/or symbolequation and identify similarities withthe burning of fuels
• describe the features of alveoli andexplain how damaged alveoli result inless gas exchange.
Suggested lesson allocation (see individual lesson planning guides)Direct route
B1 Food for energy
B2 Everything respires
B3 Breathe in and out
B4 A transportsystem
B5 Trouble with yeast– Think aboutexplanations
Extra lessons (not in pupil book)
B2 Everythingrespires Extra lessonif Activity B2a doneas pupil circus
Review and assess progress(distributedappropriately)
MisconceptionsPupils often think that ‘plants photosynthesise but not respire’, hence respiration in plants is covered in this unit before photosynthesis is met inYear 9. Other misconceptions may include: we breathe in oxygen and breathe out carbon dioxide, respiration happens in the lungs, plants only respire atnight, plants breathe carbon dioxide, animals breathe oxygen, arteries carry red blood and veins carry blue blood. Emphasise that breathing and respiration have different meanings and ‘fuels’ used by cells do not burn.
Health and safety (see activity notes to inform risk assessment)In this unit, teachers should make specific risk assessments when pupils use hazardous materials and handle living animal material also when theyobserve energy released in the combustion of sugar or measure body temperature. Disinfect clinical thermometers after use.
Learning objectivesi The products of digestion are transported to the cells by the blood. ii The process by which we get energy from glucose in cells is called aerobic respiration. iii Respiration can be represented by the word equation: glucose + oxygen → carbon dioxide + water. This reaction releases energy (red only).iv In situations where oxygen supply is inadequate, respiration occurs without oxygen. This is called anaerobic respiration (red only).
Scientific enquiryv Use ICT to present quantitative data and present information. (Framework YTO Sc1 8d) vi Make a prediction. (Framework YTO Sc1 7b)
Suggested alternative starter activities (5–10 minutes)
Introduce the unit
Unit map for Respiration.
Share learning objectives
• Find out that respirationgives us energy and usuallyneeds oxygen.
• Find out that respiration canhappen without oxygen.
• Record results in a suitableformat. (Sc1)
Problem solving
Pupils compare the labels of different groups of high-energy drinks andsnacks.
Brainstorming
Pupils make a list of whichnutrients are essential inthe diet and recap theirfunctions in the body, fromunit 8A.
Capture interest
Demonstrate that a lemonis a store of electricalenergy.
Suggested alternative main activitiesActivity
Textbook B1
Activity B1a ICT
Activity B1b Practical
Activity B1c Practical
Activity B1d CatalystInteractive Presentations 2
Learningobjectivesee above
i, ii, iii andiv
i, ii, iii, ivand v
i, ii, and iii
i, ii, iii, iv, v and vi
i, ii, iii andiv
Description
Teacher-led explanation and questioning OR pupils work individually,in pairs or in small groups through the in-text questions and thenonto the end-of-spread questions if time allows.
What is respiration? Pupils prepare a leaflet or Power Point®presentation on respiration to reinforce the concepts covered in thebook spread.
Hands up! Pupils compare their ability to clench their fist repeatedlyabove and below their heads, explaining the results in terms of bloodsupply, and aerobic/anaerobic respiration.
Exercise and your heart rate In pairs, pupils measure each other’sheart rate before exercise, and then 30, 60 and 90 seconds afterexercise. They make a prediction, present their results using aspreadsheet and explain why their breathing rate increases afterexercise.
Support animation of the book-spread diagram about respiration.
Approx.timing
20 min
30 min
25 min
45 min
10 min
Target group
C H E S
R/G G R S
✔ ✔
✔ ✔
✔ ✔
✔
Suggested alternative plenary activities (5–10 minutes)
Review learning
Flashcard activity about theequation for respiration.
Sharing responses
Share predictions, resultsand conclusions for ActivityB1c.
Group feedback
Pupils present their PowerPoint® presentations fromActivity B1a.
Word game
Play Snap! with wordsabout respiration.
Looking ahead
Ask pupils to write a shortpoem about respiration.
Learning outcomes
Most pupils will …
• describe aerobic respiration as a reaction withoxygen
• describe some effects of inadequate oxygen supply • use Power Point® to give a presentation on
respiration.
Some pupils, making less progress will …
• recognise that oxygen is required foraerobic respiration and that oxygen andglucose are transported in the blood
• use Power Point® to give a presentation on respiration with help.
Some pupils, making more progress will …
• represent the process of aerobic respiration asa word and/or symbol equation and identifysimilarities with the burning of fuels
• explain anaerobic respiration including lacticacid formation.
Learning objectivesi Plants and other animals release energy from food in the same way as we do. ii Respiration takes place in every cell of a plant.
Scientific enquiryiii Understand the need to use a control. (Framework YTO Sc1 8e) iv Make observations, record them and identify patterns in data. (Framework YTO Sc1 7d, f)
Suggested alternative starter activities (5–10 minutes)
Recap last lesson
Play the ‘Taboo’ game torecap the main ideas fromlast lesson.
Share learningobjectives
• Find out about respirationin other animals andplants.
• Be able to collect resultsand record them in asuitable format. (Sc1)
Brainstorming
Recap the characteristics oflife from KS2.
Problem solving (1)
Pupils do a true/false quizto check misconceptionsabout respiration in otherorganisms.
Problem solving (2)
Pupils identify those thingsfrom the slideshow thatrespire.Catalyst InteractivePresentations 2
Suggested alternative main activitiesActivity
Textbook B2
Activity B2a Practical
Activity B2b Practical
Learningobjectivesee above
i and ii
i, ii, iii andiv
i, ii and iv
Description
Teacher-led explanation and questioning OR Pupils work individually,in pairs or in small groups through the in-text questions and thenonto the end-of-spread questions if time allows.
Do plants respire? Teacher demonstration (or pupil practical circus):a. Investigate whether cress seeds need oxygen in order to
germinate.b. Investigate whether germinating peas produce carbon dioxide.c. Investigate whether plant leaves produce waterd. Investigate whether germinating pea seeds release energy in the
form of heat.
Which part respires most? Pupils dissect a plant to produce a muslinbag of stem pieces, root pieces, and leaf pieces. By hanging the bag ina flask containing indicator, they can work out which respires the most.
Approx.timing
20 min
35 min
35 min
Target group
C H E S
R/G G R S
✔ ✔
✔
Suggested alternative plenary activities (5–10 minutes)
Learning objectivesi The lungs are specialised organs where oxygen from the air enters the blood and carbon dioxide passes out. ii The air we breathe in has more oxygen and less carbon dioxide than the air we breathe out. iii Gas exchange happens when oxygen moves from the lungs into the blood and carbon dioxide moves out of the blood into the lungs (diffusion
red only). iv The alveoli provide a large surface area for this gas exchange (red only).
Scientific enquiryv Make comparisons between inhaled and exhaled air. vi Present findings in a suitable format. (Framework YTO Sc1 7f)
Suggested alternative starter activities (5–10 minutes)
Recap last lesson
Select four volunteersto talk about respirationfor up to 1 minute.
Share learning objectives
• Find out about how the lungs work to help us breathe.
• Find out about how we get oxygen into ourbodies and carbon dioxide out of our bodies.
• Be able to make comparisons betweeninhaled and exhaled air.
Problem solving
Demo the ‘Pub’ gameof transferring liquidinto a glass byburning the oxygen.
Capture interest (1)
Show an animation tointroduce the idea thatthe alveoli provide alarge surface area.Catalyst InteractivePresentations 2
Capture interest (2)
Use lung capacity bagsto measure students’vital and tidal capacity.
Suggested alternative main activitiesActivity
Textbook B3
Activity B3a Practical
Activity B3b Practical
Activity B3c Discussion
Activity B3d CatalystInteractive Presentations 2
Activity B3e CatalystInteractive Presentations 2
Learningobjectivesee above
i, ii, iiiand iv
ii and v
i, iv and vi
iii and vi
i and iv
iii
Description
Teacher-led explanation and questioning OR Pupils work individually, inpairs or in small groups through the in-text questions and then onto theend-of-spread questions if time allows.
Air in and out Pupils predict the differences between inhaled and exhaledair and then carry out a series of experiments to check their predictions.
Lung dissection Pupils observe dissection and inflation of a pig’s lung.
Gas exchange in other animals Pupils research ways in which otheranimals do gaseous exchange to produce a Power Point® presentation orinformation leaflet.
Interactive diagram to label the respiratory system
Support animation of gas exchange happening.
Approx.timing
20 min
35 min
20 min
40 min
10 min
15 min
Target group
C H E S
R/G G R S
✔
✔
✔
✔
✔
Suggested alternative plenary activities (5–10 minutes)
Review learning
Play ‘What happens next?’to describe the passage ofair into the lungs.
Sharing responses
Collate ideas from ActivityB3a.
Group feedback
Share ideas from ActivityB3c in small groups.
Word game
Check progress by playingthe loop game with keyideas so far.
Looking ahead
True/false game withteacher reading statementsto pupils.
Learning outcomes
Most pupils will …
• label a diagram of the respiratory system to showstructure and route taken by the air
• relate the structure of the alveoli to their function • describe how oxygen and carbon dioxide are
exchanged at the surface of an alveolus and thedifferences between inhaled and exhaled air.
Some pupils, making less progress will …
• label a diagram of the respiratory system to showstructures and route taken by the air with help
• state some of features of the alveoli • state that oxygen and carbon dioxide are
exchanged at the surface of an alveolus and thedifferences between inhaled and exhaled air.
Some pupils, making more progresswill …
• explain gas exchange in terms ofdiffusion
• explain how the alveoli provide a largesurface area for this gas exchange
• describe how damaged alveoli result inless gas exchange.
Key wordsblood vessels, breathing, alveoli, gas exchange, red only: emphysema, respiratory system, diffusion
Out-of-lesson learningHomework B3 Textbook B3 end-of-spread questions Activity B3c Find out what happens in the airways of asthma sufferers. Find out about first aid techniques for artificial ventilation. Visit an aquarium and find out from attendants how animals exchange gases in water.
Learning objectivesi The blood transports oxygen from the lungs to the cells and carbon dioxide from the cells to the lungs. ii The heart is a muscular, double pump, one side supplies the lungs with blood, the other supplies the body organs.
Scientific enquiryiii Consider early ideas about circulation including how and why these ideas have changed and developed. (Framework YTO Sc1 8a) iv Use a model to understand blood circulation. (Framework YTO Sc1 8a)
Suggested alternative starter activities (5–10 minutes)
Recap last lesson
Show an interactiveanimation of gaseousexchange at the alveolus.Catalyst InteractivePresentations 2
Share learningobjectives
• Find out about what theblood does.
• Find out about how theheart works.
• Find out how scientificideas about the heart havechanged over the last fewhundred years. (Sc1)
Problem solving
Ask pupils to measure theirbreathing and heart ratebefore and after exercise.
Capture interest (1)
Pupils hold a hand in theair by their side, and thenabove their head, andrepeatedly clench their fistas many times as possiblein 2 minutes. Avoid, if havedone Activity B1b.
Capture interest (2)
Show a ‘x-ray’ photo ofsomeone with radioactivetracer in their blood.Catalyst InteractivePresentations 2
Suggested alternative main activitiesActivity
Textbook B4
Act B4a Discussion
Activity B4b Paper
Learningobjectivesee above
i, ii and iii
i, ii and iv
i
Description
Teacher-led explanation and questioning OR Pupils work individually,in pairs or in small groups through the in-text questions and thenonto the end-of-spread questions if time allows.
Round and round Pupils model the way that oxygen and carbondioxide move around the body via the heart and lungs.
Transport for respiration Pupils answer questions based on passageabout red blood cells and blood vessels.
Approx.timing
20 min
15 min
20 min
Target group
C H E S
R/G G R S
✔
✔
Suggested alternative plenary activities (5–10 minutes)
Review learning
Show pupils the slideshowabout the effects ofsmoking on the lungs.Catalyst InteractivePresentations 2
Sharing responses
As a class, ask pupilsquestions to make learningexplicit from the circulationgame Activity B4a.
Group feedback
In groups, pupils comparetheir answers to ActivityB4b.
Word game
Ask pupils to write a set ofdirections for the blood tonavigate around thecirculation.
Looking back
Pupils revise andconsolidate knowledge fromthe unit.
Learning outcomes
Most pupils will …
• describe the role of blood in transportingcarbon dioxide from, and oxygen to the lungs
• explain why tissues need a good blood supplyand how the circulatory system maintains this
• describe an earlier model of circulationindicating how it does not match present-dayevidence.
Some pupils, making less progress will …
• recognise that the blood transports oxygen andglucose
• describe how the circulatory system maintainsa good blood supply to the tissues
• recognise that ideas about circulation havechanged.
Some pupils, making more progresswill …
• describe and explain some of the evidenceleading to present-day ideas about how andwhy blood circulates.
Key wordsarteries, veins, capillaries, red only: circulatory system
Out-of-lesson learningHomework B4 Textbook B4 end-of-spread questions Activity B4b Find out about the causes and effects of coronary heart disease.
Learning objectivesi Other organisms than humans respire. The structure of this lesson is based around the CASE approach. The starter activities give concrete preparation. The main activities move away from theconcrete towards a challenging situation, where pupils need to think. The extended plenary gives pupils time to discuss what they have learnt, to negotiatea method to commit to paper and express their ideas verbally to the rest of the class.
Scientific enquiryii A hypothesis is an idea that explains why something happens. iii A prediction states what will happen if the hypothesis is right. iv Evidence is what actually happens. It proves or disproves the hypothesis.
Suggested alternative starter activities (5–10 minutes)
Bridging to the unit
Demonstrate yeast bubbling carbondioxide through limewater.
Setting the context
Pupils identify the evidence theywould need to come to particularconclusions.
Concrete preparation (1)
Ask pupils to make a predictionabout what happens if you warmup a chemical reaction, and toexplain why.
Concrete preparation (2)
Show an interactive animation inwhich pupils can control thetemperature. Catalyst Interactive Presentations 2
Suggested main activitiesActivity
Textbook B5
Activity B5a Practical
Learningobjectivesee above
i, ii, iii andiv
i, ii, iii andiv
Description
Teacher-led explanation and questioning OR Pupils work individually,in pairs or in small groups through the in-text questions and thenonto the end-of-spread questions if time allows.
Is yeast a chemical? Demonstration of the yeast investigation thecharacters in the book spread carried out.
Approx.timing
30 min
35 min
Target group
C H E S
R/G G R S
✔
Suggested alternative plenary activities (5–10 minutes)
Group feedback
Discuss the stages involved in carrying out an investigation, includingmaking a hypothesis, writing a prediction and collecting evidence.
Bridging to other topics
Using the set of situations, pupils should write down the hypothesis,alternative predictions, and the evidence to collect for each.
Learning outcomes
Most pupils will …
• recognise that a hypothesis is an idea thatexplains why something happens and that aprediction states what will happen if it isright
• discuss how evidence supports a hypothesis • resolve cognitive conflict arising when
evidence does not support the hypothesis andformulate a new hypothesis
• appreciate how we can investigate whetheryeast is living or non-living.
Some pupils, making less progress will …
• discuss a hypothesis, prediction and evidence • begin to understand how scientific
explanations can arise from suggesting andtesting a hypothesis.
Some pupils, making more progress will …
• apply the concept of making and testing ahypothesis to other contexts.
indicator Rlactic acid Roxygenplantsrespiratory system Rveinswater
Respiration
Heart Energy
FoodLungs
Unitmaps.qxd 12-Nov-03 8:56 AM Page 2
B1 StartersFood for energy
Introduce the unit● Either draw the outline of the unit map on the board then ask
pupils to give you words to add, telling you where to add them.Suggest some words yourself when necessary to keep pupils on theright track.
● Or give out the unit map and ask pupils to work in groups,deciding how to add the listed words to the diagram. Then gothrough it on the board as each group gives suggestions.
Share learning objectives● Ask pupils to write a list of FAQs they would put on a website
telling people about food and energy. Collect suggestions as awhole-class activity, steering pupils towards those related to theobjectives. Conclude by highlighting the questions you wantthem to be able to answer at the end of the lesson.
Problem solving● Get pupils and other members of staff to collect packaging in
advance from different brands of high-energy drinks and snacks(such as high-energy sweets or Kendal mint cake).
● Arrange the packaging into groups so that each group contains twodrinks and one snack.
● Get pupils to work in pairs or threes on each group of packaging.Tell them that glucose provides energy, and ask them torecommend which group of high-energy foods a tennis playermay want to take onto court, by looking at the nutritional labels.
Brainstorming● Pupils make a list of which nutrients are essential in the diet.
● Ask them to write down their ideas about the function of eachnutrient in the body.
● As a class, make explicit those nutrients that are stores of energy,and outline the functions of any others they suggest.
Capture interest● Ask the pupils if they think a lemon is a store of energy.
● Set up the lemon juice cell described on the teacher sheet.
● Connect the circuit to the switch on the clock.
● Use the demonstration to show that foods are stores of energy.You may want to explain that a chemical reaction takes place thatconverts the stored energy into electrical energy.
● If you want to, you can also weigh the lemon before and after toprove that energy is not ‘stuff’ and has no mass.
Suggested alternative starter activities (5–10 minutes)
Introduce the unit
Unit map for Respiration.
Share learning objectives
• Find out that respiration gives us energyand usually needs oxygen.
• Find out that respiration can happenwithout oxygen.
• Record results in a suitable format. (Sc1)
Problem solving
Pupils compare the labelsof different groups of high-energy drinks and snacks.
Brainstorming
Pupils make a list ofwhich nutrients areessential in the diet andrecap their functions inthe body, from Unit 8A.
Capture interest
Demonstrate thata lemon is a storeof electricalenergy.
Sheet 1 of 1
B-Starters(01-10).qxd 29-Sep-03 2:18 PM Page 1
B1 StartersFood for energy
Capture interestTeacher sheetThe method below describes how to set up a lemon-powered clock.
● Wrap each strip of cardboard in aluminium foil.
● Cut a slit into each lemon, insert one of the strips of aluminium and attach a paper clip tothe top.
● Cut another slit next to the first and insert the copper tubing. Do not let the copper (Cu)and aluminium (Al) touch each other.
● Wire your lemons into a circuit, as follows:– Connect the aluminium in lemon 1 to the copper in lemon 2.– Connect the aluminium in lemon 2 to the copper in lemon 3.– Attach one wire to the copper in lemon 1, and leave the other end free.– Attach one wire to the aluminium in lemon 3, and leave the other end free.
● Tape the free end of the wire from lemon 1 to the clock’s positive terminal and the free endof the wire from lemon 3 to the negative terminal.
● Within a minute or so, the clock should start to run.
● Use the results to discuss the idea that foods act as a store of energy.
Recap last lesson● Pupils play Taboo using cards cut out from the pupil
sheet.
● Give one pupil a card with a mystery word on it. Thepupil offers clues to the class to allow them to identify themystery word, but is not allowed to use the given ‘taboo’words in their clues.
● You can adjust the level of challenge by banning the useof different words in the taboo list.
Share learning objectives● Ask pupils to write a list of FAQs they would put on a
website telling people about respiration in plants andother animals. Collect suggestions as a whole-classactivity, steering pupils towards those related to theobjectives. Conclude by highlighting the questions youwant them to be able to answer at the end of the lesson.
Brainstorming● Recap the characteristics of life with pupils. Use the
discussion to introduce the idea that all living thingsrespire.
Problem solving (1)● Pupils do the true/false quiz to check misconceptions
about respiration in other organisms.
Problem solving (2)● Show pupils the slideshow of photos.
● Ask pupils to write down which of the things in thephotos respire.
● Go through the answers as a class, reminding pupils thatrespiration is one of the features of all living things.
Recap last lesson● Ask four volunteers to come up to the front of the class.● Ask one of them to begin to speak about respiration without
repeating any words.● If they do repeat a word, the rest of the class can challenge
them, and the next volunteer takes over.● Whoever talks for longest without a successful challenge is the
winner.
Share learning objectives● Ask pupils to write a list of FAQs they would put on a website
telling people about breathing and gas exchange. Collectsuggestions as a whole-class activity, steering pupils towardsthose related to the objectives. Conclude by highlighting thequestions you want them to be able to answer at the end ofthe lesson.
Problem solving● Display the equipment listed on the right and explain the
challenge.● Take ideas from the class and discuss them. Then demonstrate
the solution.● Explain to the class that when something burns, it uses up
oxygen, and that oxygen makes up about one-fifth of the air.● Measure the volume of the glass that has been filled up with
oxygen to confirm that it is approximately one-fifth of thevolume.
● Introduce the other gases that make up the other four-fifths ofthe air.
Capture interest (1)● Show the animation of the alveoli folding out and coalescing.● Use it to show the large surface area available in the lungs.
Capture interest (2)● As a class, ask pupils to decide which three pupils have the
biggest lungs.● If you have them, use lung capacity bags, 5 litre measuring
cylinders, or a graduated bell jar to measure pupils’ vital andtidal capacity.
● Discuss the differences between the pupils’ lung capacities.Explain that athletes tend to have larger lungs, and ask pupilsto suggest why this may be the case.
➔ Teacher sheet
Equipment1 box of matches, pile of coins 5cmhigh, shallow dish that resembles awide pub ashtray (it must hold150ml of water not more than 5cmdeep and have a flat bottom), pintglass (or equivalent with aneven rim).
Problem solvingTeacher sheetEnsure the shallow dish contains 150ml of water before youintroduce the equipment to the class. Having shown themthe equipment available, set the following challenge topupils:
Move the water from the dish, into the glass, withouttouching the dish.
Take ideas either as a class, or from small-group discussions.
The way to do it is as follows:
1 Pile up the coins in the dish.
2 Balance three matches on top so they are clear of thewater.
3 Use a fourth match to light them together.
4 Invert the glass over the top.
5 Watch the water move into the glass.
Use the results to point out that oxygen has been burnt and removed from the airin the glass. The space remaining then fills with water.
This space should be approximately one fifth of the volume of the glass as oxygenmakes up one fifth of the volume of the air.
For your own information, consumption of oxygen only accounts for part of thevolume. The rest is accounted for by pressure changes as the warm air cools.
Keep the box of matches under your control or in a secure place.
pile ofcoins
Invert glass overburning matches
B-Starters(01-10).qxd 29-Sep-03 2:19 PM Page 7
B4 StartersA transport system
Recap last lesson● Either in small groups, or as a class, use the interactive
animation of gas exchange.
Share learning objectives● Ask pupils to write a list of FAQs they would put on a
website telling people about the blood system. Collectsuggestions as a whole-class activity, steering pupilstowards those related to the objectives. Conclude byhighlighting the questions you want them to be able toanswer at the end of the lesson.
Problem solving● In pairs, ask pupils to measure their breathing rate and
heart rate.
● Do one minute jogging up and down on the spot.
● Measure both breathing rate and heart rate again.
● Remind pupils of why breathing rate increases andintroduce the idea of why the heart rate also increases,which they may have already seen in Activity B1c.
Capture interest (1)● Pupils hold one hand down by their side and repeatedly
clench their fist as many times as possible in twominutes. Record the number of clenches.
● Rest for 2–3minutes, and then repeat with the samehand, but with their hand up in the air above theirhead.
● Use their responses to introduce the importance of theblood in carrying oxygen.
Capture interest (2)● Show the ‘x-ray’ video of someone with radioactive
tracer in his or her blood.
● Highlight the way in which the blood system spreadsthroughout the body.
➔ Catalyst Interactive Presentations 2
Safety NoteAvoid undue competition developingduring exercises. Be aware of any studentexcused PE on medical grounds who maynot be able to take part. Asthma sufferersmay need to use an inhaler before theyexercise.
Safety noteWarn pupils to slow down their clenches iftheir hand starts to hurt.
Suggested alternative starter activities (5–10 minutes)
Recap last lesson
Show an interactiveanimation of gaseousexchange at the alveolus.Catalyst InteractivePresentations 2
Share learning objectives
• Find out about what the blood does.• Find out about how the heart works.• Find out how scientific ideas about
the heart have changed over the lastfew hundred years. (Sc1)
Problem solving
Ask pupils tomeasure theirbreathing andheart rate beforeand after exercise.
Capture interest (1)
Pupils hold one hand down bytheir side, and then above theirhead, and repeatedly clenchtheir fist as many times aspossible in two minutes. Avoid,if have done Activity B1b.
Capture interest (2)
Show the ‘x-ray’ video ofsomeone with radioactivetracer in their blood.Catalyst InteractivePresentations 2
B-Starters(01-10).qxd 29-Sep-03 2:19 PM Page 8
B5 StartersTrouble with yeast – Think about
Bridging to the unit● Demonstrate yeast bubbling carbon dioxide through
limewater.
● Confirm with pupils that yeast respires.
Setting the context● Pupils identify the evidence they would need to
collect to come to the conclusions opposite.
Concrete preparation (1)● In small groups, ask pupils to discuss what would
happen if you warm up a chemical reaction.
● Pupils should write down a formal prediction andtry to explain it.
Concrete preparation (2)● Either as a class, or in small groups (depending on
available computers), pupils use the animation andcontrol the temperature to see its effect on the rateof a generic reaction.
● Ask pupils to make a prediction before they startworking with the animation.
➔ Teacher sheet
Equipmentboiling tube, paraffin oil, yeast suspension in5% glucose solution warmed until bubbling,delivery tubing, test tube with 2cm depthlimewater.
ConclusionsA larger amount of yeast will respire morequickly.
A larger amount of glucose will help the yeastto respire more quickly.
Running the activityMany pupils will be experienced in the use of word processing and Power Point®.The Help sheet provides some pointers (which may be useful for all pupils) to helpstructure their leaflet and to ensure they include all of the main ideas.
ICT opportunitiesPupils use Power Point® or a word processor to prepare a leaflet on respiration,summarising their learning from the Pupil book.
They could also be encouraged to use the Internet to find out more informationabout respiration using the websites below:
Respiration is a very important process that happens in all livingthings. It is the way in which our bodies release energy from thefood we eat.
You are going to produce a leaflet or presentation to tell otherpupils about respiration.
You will need to give information that answers these questions. Youcould even use the questions as headings.
● What is respiration?● Which nutrients in your food give you energy?● What does respiration need?● What does respiration make?● What does respiration release?● Why does your heartbeat get faster if you exercise?
Use your textbook to get the information. You may also want to usethe Internet to find more information.
Running the activityPupils put their hands down by their sides and repeatedly clench their fists. They shouldcount how many clenches they can do before their hand begins to ache. They shouldthen rest their hand for one minute, and repeat but with their hand above their head.
Core: Pupils explain the results in terms of blood supply to the hand and respiration.
Extension: Pupils should also be able to explain the results by discussing anaerobicrespiration.
Expected outcomesAll pupils should record the number of hand clenches they can do with their handabove their head and by their side and explain their results in terms of lack of oxygen oranaerobic respiration.
PitfallsEnsure pupils begin with their hands down by their side. If they begin with their handabove their head, they can get unexpected results. This is because their hand is tiredbefore they start hand clenching by their side.
AnswersCore:1 B
2 B
3 B
4 B
5 When your hand is above your head, the flow of blood is reduced. This means thesupply of glucose and oxygen to the cells is limited, they respire less, and release lessenergy. Therefore, the cells get tired more quickly and ache more readily. Pupils mayalso account for their results by discussing anaerobic respiration (see Extension).
Extension:1 Hand below.
2 Hand below.
3 Hand below.
4 Hand below.
5 Hand above.
6 Because lactic acid is produced.
7 Because it releases energy even without the presence of oxygen.
Type Purpose DifferentiationPractical Pupils learn about the importance of blood in carrying the reactants for respiration. Core, Extension
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B1bTechnician
activity notesHands up!
Equipment ● Stopwatch
For your informationRunning the activityPupils put their hands down by their sides and repeatedly clench their fists. Theyshould count how many clenches they can do before their hand begins to ache.They should then rest their hand for one minute, and repeat but with their handabove their head.
Core: Pupils explain the results in terms of blood supply to the hand andrespiration.
Extension: Pupils should also be able to explain the results by discussing anaerobicrespiration.
Expected outcomesAll pupils should record the number of hand clenches they can do with their handabove their head and by their side and explain their results in terms of lack ofoxygen or anaerobic respiration.
PitfallsEnsure pupils begin with their hands down by their side. If they begin with theirhand above their head, they can get unexpected results. This is because their handis tired before they start hand clenching by their side.
To get energy, your cells need glucose and oxygen forrespiration. You are going to find out how important your bloodsupply is in supplying your cells with glucose and oxygen.
Obtaining evidence
1 If you are right-handed, put your right arm down by your side.If you are left-handed, do the same with your left hand.
2 Count how many times you can clench your fist before it startsto ache.
3 Wait for five minutes, and then repeat with the same arm aboveyour head.
Considering the evidence
For 1 – 4 , write either A or B.
A When my hand is above my head.B When my hand is down by my side.
1 When do you think it is easier for blood to get to your hand?2 Blood carries glucose and oxygen. When does your hand get a
better supply of oxygen and glucose?3 When do the cells in your hand respire more?4 When do you think the cells in your hand can release the most
energy?5 Write a short paragraph to explain why Jack’s hand ached more
quickly when his hand was above his head. To help you, use youranswers to 1 – 4 , and any additional scientific knowledge.
To get energy, your cells need glucose and oxygen for respiration.You are going to find out how important your blood supply is insupplying your cells with glucose and oxygen.
Obtaining evidence
1 If you are right-handed, put your right arm down by your side.If you are left-handed, do the same with your left hand.
2 Count how many times you can clench your fist before it startsto ache.
3 Wait for five minutes, and then repeat with the same arm aboveyour head.
Considering the evidence
When do you think it is easier for blood to get to your hand?Blood carries glucose and oxygen. When does your hand get a fastersupply of oxygen and glucose?When do the cells in your hand carry out more aerobic respiration?When do the cells in your hand release the most energy from aerobicrespiration?Anaerobic respiration happens when the cells in your hand run out ofoxygen. In which case did they run out of oxygen most quickly?Explain why your hand aches when anaerobic respiration happens?If anaerobic respiration makes your hand ache, it might seem oddthat your hand should respire anaerobically. Explain how the cells inyour hand benefit from respiring anaerobically.Write down the word equation for anaerobic respiration in the cells ofyour hand.
Running the activityCore: Pupils work in pairs. Each pupil should carry out the activity and gather their own results. Pupilsshould begin by finding each other’s pulse rate at rest. They should measure it again after 30, 60 and90seconds of exercise. Ensure pupils begin with the shortest amount of exercise first. You can decide uponthe type of exercise appropriate to your school circumstances (but see the safety note below). Ask pupils toplot their data and draw a graph using a spreadsheet.
Help: Pupils carry out a similar practical, but the Help sheet supports them in making a prediction,designing the spreadsheet, and drawing a conclusion. They can either follow the instructions for theexperiment on the Core sheet, or the teacher may show them what to do.
Other relevant materialSkill sheet 5: Drawing charts and graphs Skill sheet 26: Designing a spreadsheetSkill sheet 6: Interpreting graphs Skill sheet 27: Graphs with a spreadsheet
Expected outcomesPupils measure their pulse rates at rest, and then after exercising for 30, 60, 90 and 120seconds.
Core: Pupils should predict what would happen to their pulse rate with increasing amounts of exercise.They enter their results in a spreadsheet they create and plot a graph. Their conclusion should explain theirresults in terms of glucose and oxygen supply.
Help: This helps pupils to predict what would happen to their pulse rate with increasing amounts ofexercise, to design a spreadsheet to record their results and plot a graph, and to explain their results interms of glucose and oxygen supply.
Safety notesTake advice from PE staff about appropriate exercise and warm-up exercises. Ensure pupils are in footwearappropriate to the exercise chosen. Be aware of any students excused from PE who may not be able to takepart. Asthmatics may need to use their inhalers.
ICT opportunitiesPupils use a spreadsheet for their results and graphs.
AnswersCore:
As the amount of time I spend exercising increases, my heart rate will also increase.
As the amount of time I spent exercising increased, my heart rate also increased.
When I exercise, my muscles need more energy, my muscle cells need to respire more, and they needmore oxygen and glucose. To supply more oxygen and glucose, my heart beats faster to pump blood tomy muscles more quickly.
Help:As I do more and more exercise, I think my heart rate will get faster.
As the time spent exercising gets longer, my pulse rate gets faster.
Type Purpose DifferentiationPractical Pupils measure each other’s heart rate before and after exercise and explain why their
heart rate increases.Core, Help
1
2
3
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B1cTechnician
activity notesExercise and your heart rate
Other relevant materialSkill sheet 5: Drawing charts and graphsSkill sheet 6: Interpreting graphsSkill sheet 26: Designing a spreadsheetSkill sheet 27: Graphs with a spreadsheet
EquipmentFor each group:● stopwatch● computer with spreadsheet
For your informationRunning the activityCore: Pupils work in pairs. Each pupil should carry out the activity and gather theirown results. Pupils should begin by finding each other’s pulse rate at rest. Theyshould measure it again after 30, 60 and 90seconds of exercise. You can decideupon the type of exercise appropriate to your school circumstances (but see thesafety note below). Ask pupils to plot their data and draw a graph using aspreadsheet.
Help: Pupils carry out a similar practical, but the Help sheet supports them inmaking a prediction, designing the spreadsheet, and drawing a conclusion. Theycan either follow the instructions for the experiment on the Core sheet, or theteacher may show them what to do.
Expected outcomesPupils measure their pulse rates at rest, and then after exercising for 30, 60, 90 and120seconds.
Core: Pupils should predict what would happen to their pulse rate with increasingamounts of exercise. They enter their results in a spreadsheet they create and plota graph. Their conclusion should explain their results in terms of glucose andoxygen supply.
Help: This helps pupils to predict what would happen to their pulse rate withincreasing amounts of exercise, to design a spreadsheet to record their results andplot a graph, and to explain their results in terms of glucose and oxygen supply.
PitfallsEnsure pupils begin with the shortest amount of exercise first.
Safety notesTake advice from PE staff about appropriate exercise and warm-up exercises.Ensure pupils are in footwear appropriate to the exercise chosen. Be aware of anystudents excused from PE who may not be able to take part. Asthmatics may needto use their inhalers.
In this activity, you are going to find out what happens to yourbody during exercise.
Equipment
● stopwatch● computer with spreadsheet
Planning and predicting
In this activity, you are going to do some exercise. Write downwhat you think will happen to your heart rate as you do more and more exercise.
Obtaining evidence
1 Prepare a table for your results with columns for ‘Time spentexercising’ and ‘Pulse rate’.
2 In pairs, measure each other’s heart rates when you are at rest.You can do this by taking the pulse either at the wrist or in theneck. Count the number of beats in 20seconds, and thenmultiply your answer by three. This gives you the heart rate inbeats per minute.
3 Decide which one of you is to go first. Exercise for 30secondsand record your pulse rate immediately having finished theexercise.
4 Allow your pulse rate to go back to normal, and then exercise for60seconds. Take your pulse rate immediately having finished theexercise.
5 Repeat step three but exercise for 90seconds and 120secondsinstead.
Presenting the results
6 Enter your results into a spreadsheet. Use your results table tohelp you design the spreadsheet.
7 Use the spreadsheet to help you draw a graph of amount ofexercise vs heart rate.
Considering the evidence
Describe the pattern you have found in your results.By using ideas about respiration, glucose and oxygen, explain thepattern you have found in your results.
Use this sheet to help you record your prediction, results and conclusions for this activity.
Planning and predicting
1 Write down what you think will happen to your heart rate as you do more and more exercise.As I do more and more exercise, I think my heart rate will
Obtaining evidence
1 Use the table below to record your resting heart rate (pulse rate) and then the heart rate after exercising.
Presenting the results
2 Set up a spreadsheet with the same columns and rows as your results table and enter your results.
3 Use the spreadsheet to draw a graph of time spent exercising vs heart rate.
Considering the evidence
2 Describe the pattern you have found in your results by crossing out the word that is wrong in the sentence below.As the time spent exercising gets longer, my heart rate gets faster/slower.
3 Fill in the gaps below to help explain the pattern in your results.
If I exercise more, my muscles need more e
To get more energy, my muscle cells need to r more.
To respire more, my muscle cells need more and
To supply more oxygen and glucose, my heart beats faster. The heart
pumps more blood to the . Because the blood carries
oxygen and glucose, this means the muscle cells can respire more.
Time spent exercising Heart rate after exercise(seconds) (beats per minute)
0 (at rest) Resting heart rate =
30
60
90
120
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B2aTeacher
activity notesDo plants respire?
Running the activityRun the experiments shown on the Technician sheet as a demonstration to the whole class. You will needto set up Experiment A and D several days before the lesson. You will also need to explain how eachexperiment is designed to produce a conclusion, particularly focusing on the role of bromothymol blue(detects carbon dioxide), alkaline pyrogallol (absorbs oxygen) and cobalt chloride (detects water).
Core: Pupils fill in their observations on the Core sheet during the demo and then draw conclusions.
Help: Pupils will need access to the Core sheet for the results table. The Help sheet provides a writing frameto help them draw conclusions.
Expected outcomesCore: Pupils record their observations and conclude that plants respire in the same way as humans.
Help: Pupils complete the sentences to help them draw conclusions.
PitfallsSometimes the peas do not release enough heat to register on the thermometer. To ensure an appropriateresult, pour a little warm water into the flask with the live peas to increase the temperature by 1–2°C.
If you forget to put the lid back on the container with the cobalt chloride paper, it will turn pink anyway,and spoil the rest of your practical. You may need to leave experiment B over a longer period to getconclusive results.
Safety notesEye protection is needed. Ensure pupils cannot gain access to the alkaline benzene-1,2,3-triol (pyrogallol)or the bromothymol blue. You can replace the pyrogallol with lab iodine solution, but boil the peas in thatflask before use to ensure they will not germinate. Do not let pupils touch the cobalt chloride paper as it isa mild carcinogen.
ICT opportunitiesIt would be possible to use datalogging to measure the change in colour of the bromothymol blue.
Answers – Core
1 We know plants respire because they use up oxygen, produce carbon dioxide and water, and release energy.
Help:1 A oxygen, B carbon dioxide, C water, pink, D energy.
For your informationRun these practicals as a demonstration to the whole class. You will need to set upExperiments A and D several days before the lesson.
You will also need to explain how each experiment is designed to produce aconclusion, particularly focusing on the role of bromothymol blue (detects carbondioxide), alkaline pyrogallol (absorbs oxygen) and cobalt chloride (detects water).
Core: Pupils fill in their observations on the Core sheet during the demonstrationand then draw conclusions.
Help: Pupils will need access to the Core sheet for the results table. The Help sheetprovides a writing frame to help them draw conclusions.
Expected outcomesCore: Pupils record their observations and conclusions and conclude that plantsrespire in the same way as humans.
Help: Pupils complete the sentences to help them draw conclusions.
PitfallsSometimes the peas do not release enough heat to register on the thermometer.To ensure an appropriate result, pour a little warm water into the flask with thelive peas to increase the temperature by 1–2°C.If you forget to put the lid back on the container with the cobalt chloride paper, itwill turn pink anyway, and spoil the rest of your practical.
Safety notesEye protection is needed. Ensure pupils cannot gain access to the alkalinebenzene-1,2,3,-triol (pyrogallol) or the bromothymol blue. You can replace thepyrogallol with lab iodine solution, but boil the peas in that flask before use toensure they will not germinate. Do not let pupils touch the cobalt chloride paperas it is a mild carcinogen.
When humans respire, they use oxygen and glucose, producecarbon dioxide and water, and release energy. Plants also needenergy, but do they respire? Your teacher will carry out somedemonstrations to help you find out.
Obtaining evidence
1 Watch the demonstrations set up by your teacher. Copy the tablebelow and fill in your observations of each demonstration andyour conclusions.
Considering the evidence
Write a short paragraph to describe your conclusion. Start theparagraph with the words: We know plants respire because …
Running the activityPupils set up three flasks as shown and leave them for at least one hour.
Each muslin bag should contain pieces of leaf,stem or root. Discuss with pupils why it isimportant that all three bags have about thesame mass and why it is necessary to have thesame volume of limewater in each flask.
Expected outcomesPupils should find that one part of the plantrespires more than the others. This can differdepending on the species, and on the size andsurface area of the pieces they choose.
PitfallsPupils may get different results from oneanother if they have used different masses, orpieces of plant of different surface area. Useany discrepancy to help discuss theirevaluations.
Pupils may need to leave the apparatus set up over a longer period of time,depending on the length of your lessons.
Safety notesPupils should wash their hands after setting up and clearing away theirequipment.
ICT opportunitiesIt would be possible to use datalogging to measure the change in colour of thelimewater.
AnswersThis will vary depending on individual groups’ results.
The flask containing the limewater that had become the most cloudy.
If, for example, you put more leaves into one of the flasks, the limewater maygo more cloudy, even though each cell in the leaves actually respires less thaneach cell in the roots or stems.
Amount of limewater. If one flask had more limewater, it would not go ascloudy, even with the same amount of carbon dioxide produced.
The pieces may have different surface areas, which would affect how easilycarbon dioxide escaped from the pieces of root, stem and leaves.
Type Purpose DifferentiationPractical Pupils carry out a practical to establish which part of a plant respires the most. Extension
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B2bTechnician
activity notesWhich part respires most?
EquipmentFor each group:● three conical flasks and bungs● three 10-cm pieces of cotton● three muslin sheets (10cm × 10cm)● limewater● one plant cut up into small pieces of leaf, root and stem [a geranium would be
fine, although you could use rapid cycling brassicas (available from Science andPlants for Schools)]
● access to an electronic balance
For your informationRunning the activityPupils set up three flasks as shown and leavethem for at least one hour.
Each muslin bag should contain pieces of leaf, stem or root. Discuss with pupilswhy it is important that all three bags have about the same mass and why it isnecessary to have the same volume of limewater in each flask.
Expected outcomesPupils should find that one part of the plant respires more than the others. Thiscan differ depending on the species, and on the size and surface area of the piecesthey choose.
PitfallsPupils may get different results from one another if they have used differentmasses, or pieces of plant of different surface area. Use any discrepancy to helpdiscuss their evaluations.
Pupils may need to leave their apparatus set up over a longer period of time,depending on the length of your lessons.
Safety notesPupils should wash their hands after setting up and clearing away theirequipment.
Just like humans and other animals, plants respire to releaseenergy. When you go for a run your muscles need more energythan your skin, and so your muscle cells respire more. You aregoing to find out which cells of a plant respire the most.
Equipment
● three conical flasks and bungs● three 10cm pieces of cotton● three muslin sheets (10cm ×10cm)● limewater● pieces of leaf, stem and root cut from a geranium in advance● access to an electronic balance
Obtaining evidence
1 Cut up parts of a leaf, stem and rootsuntil you have three piles of roughlyequal mass. You can check with anelectronic balance if you like.
2 Wrap each pile in a separate muslinbag and tie the end with cotton.
3 Set up the apparatus on the right.4 Leave the three flasks set up for the
rest of the lesson, and note anycolour changes in the limewater.
Considering the evidence
1 Which part of the plant respires the most?2 Explain how you worked this out.
Evaluating
3 Explain why it was necessary to make all of the bags the samemass.
4 What else was kept the same in every flask? Explain why it wasnecessary to keep this the same.
5 Could the shape of the pieces of leaf, stem and root haveaffected your results? If so, explain how.
Running the activityPupils make predictions about the differences between inhaled and exhaled air in terms of the substancesinvolved. Split the pupils into four groups so that each group carries out one of four activities, A–D.Alternatively, if there is time, pupils can carry out each of the experiments, or you may feel morecomfortable demonstrating some of them, particularly experiment D. Then as a whole class pool the resultsfrom the four groups and draw a conclusion about the differences between inhaled and exhaled air.
Experiment A: Oxygen Experiment B: Carbon dioxide Experiment C: Water Experiment D: Energy
Expected outcomesPupils carry out the experiments, and conclude by drawing comparisons between exhaled and inhaled air.
PitfallsPupils may forget to put the lid back on the container with the cobalt chloride paper. If this is left exposedto air, it will turn pink anyway, and spoil the rest of your practical.
Safety notesBecause limewater can bubble up the tubes, warn pupils to wear eye protection, and to avoid breathing inand out too hard. Warn them to be careful to breathe in and out of the correct tube in Experiment A.Pupils should handle the thermometers with care. They should avoid touching the cobalt chloride paperwith their fingers.
ICT opportunitiesPupils could search the Internet for the constituents of inhaled and exhaled air.
AnswersPredicting:
1 oxygen + glucose → carbon dioxide + water energy released
2 Less; more; more; more.
Experiment A
1 Air breathed in. 2 oxygen
3 Air breathed out contains less oxygen than air breathed in.
Experiment B Experiment C
1 Air breathed out. 2 Air breathed out. 1 The one that was breathed on. 2 Air breathed out.
Experiment D
1 Depends on the room. 2 Depends on the person. 3 Air breathed out.
Considering the evidence:
3
4 Air breathed out contains less oxygen than air breathed in because the body has used some of theoxygen in respiration. Air breathed out contains more carbon dioxide than air breathed in because thebody has produced carbon dioxide in respiration. Air breathed out contains more water than airbreathed in because the body has produced water in respiration. Air breathed out contains more heatenergy than air breathed in because the body has released energy in respiration.
Type Purpose DifferentiationPractical Pupils learn about the differences between exhaled and inhaled air. Core
Oxygen Carbon dioxide Water Temperature
air breathed out less more more hotter
air breathed in more less less colder
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B3aTechnician
activity notesAir in and out
EquipmentFor each group:● two test tubes with delivery tubing and bungs (see Core sheet)● access to limewater● thermometer● tweezers● two 1cm2 pieces of cobalt chloride paper● two gas jars● access to a large bowl● rubber tubing
For your informationRunning the activityPupils make predictions about the differences between inhaled and exhaled air interms of the substances involved. Split the pupils into four groups so that eachgroup carries out one of four activities, A–D. Alternatively, if there is time, pupilscan carry out each of the experiments, or you may feel more comfortabledemonstrating some of them, particularly experiment D. Then as a whole classpool the results from the four groups and draw a conclusion about the differencesbetween inhaled and exhaled air.
Experiment A: Oxygen
Experiment B: Carbon dioxide
Experiment C: Water
Experiment D: Energy
Expected outcomesPupils carry out the experiments, and conclude by drawing comparisons betweenexhaled and inhaled air.
PitfallsPupils may forget to put the lid back on the container with the cobalt chloridepaper. If this is left exposed to air, it will turn pink anyway, and spoil the rest ofyour practical.
Safety notesBecause limewater can bubble up the tubes, warn pupils to wear eye protection,and to avoid breathing in and out too hard. Warn them to be careful to breathe inand out of the correct tube in Experiment A. Pupils should handle thethermometers with care. They should avoid touching the cobalt chloride paperwith their fingers.
You are going to find out the differences between the air you breathe in andthe air you breathe out.
Predicting
Copy and complete the word equation for respiration below.
+ glucose → + energy released.
Make predictions about the air you breathe in and the air you breathe out. Copyand complete the sentences by adding the words ‘more’ or ‘less’.
Air breathed out contains oxygen than air breathed in.
Air breathed out contains carbon dioxide than air breathed in.
Air breathed out contains water than air breathed in.
Air breathed out contains heat energy than air breathed in.
Obtaining the evidence
Your teacher will give you one experiment out of four to carry out. Then you willpool your conclusions with the groups doing the other three experiments.
Considering the evidence
Copy and complete the table using the words below. You may use each wordonce, more than once or not at all.
Explain each of the differences using what you know about respiration inhumans.
You are going to find out the differences between the air youbreathe in and the air you breathe out.
Experiment A: Oxygen
1 Set up the apparatus shown in the diagram.2 Breathe out until the gas jar fills up with air.3 Put the lid on the jar while still under
water, and put the jar on a desk upsidedown with the lid against the desk.
4 Take another gas jar full of normal air(what you breathe in), and put it upsidedown on the desk.
5 Light two candles and cover them with the two gas jars. Time how long each candleburns for.
In which gas jar, ‘air breathed out’ or ‘air breathed in’, did the candle burn for longer?Which gas from the air does the candle need in order to burn?What do your answers to 1 and 2 tell you about one of the differences between airbreathed in and air breathed out?
the correct tube. Theliquid can bubble backup the tube.
Wear eyeprotection.
Be careful tobreathe gentlyin and out of
the correct tube. Theliquid can bubble backup the tube.
B-Activity(11-25).qxd 29-Sep-03 2:21 PM Page 21
B3aActivity
CoreAir in and out
You are going to find out the differences between the air youbreathe in and the air you breathe out.
Experiment C: Water
1 Take two pieces of cobalt chloride paper out of the container usingtweezers.
2 Replace the lid of the container, and take the paper back to your desk.3 Leave one piece of paper on the desk, while you breathe on the other.4 Observe the colour change (if any) that happens on each piece of paper after two
minutes.
1 Which piece of paper went pink most quickly, the one you breathed on or the one onthe desk?
2 Cobalt chloride paper turns pink in the presence of water. Which type of air containsthe most water, air breathed out or air breathed in?
You are going to find out the differences between the air youbreathe in and the air you breathe out.
Experiment D: Energy
1 Place a thermometer on the desk, and leave it there fortwo minutes. This is measuring the temperature of the air youbreathe in.
1 What is the temperature of the air you breathe in?
2 Breathe on the bulb of the thermometer for twominutes.Be careful not to touch your mouth with the thermometer.This is measuring the temperature of the air you breathe out.
2 What is the temperature of the air you breathe out?3 Temperature is a measure of the amount of heat energy. Which
contains most heat energy, air breathed out or air breathed in?
Running the activityOrder a full set of lungs from the butchers at least a week before the class. Tellthem that you want all of the organs intact when you order it. The fresher thelungs, the better they smell!
It is sensible to give squeamish pupils the opportunity not to watch the dissection,and to have something else for them to do, either in another room, or in yourclassroom away from the dissection itself.
During the dissection, outline the structure of the lungs. Include the trachea,bronchi and bronchioles in your discussion, and trace the pathway of air throughall three. Talk about the rings of cartilage on the trachea, and discuss the spongynature of the lungs.
To demonstrate how the lungs inflate, cut into the left lung slightly below theentry point of the left bronchus. There, you will find a branch of the bronchusleading to the lower part of the lung. If you insert a plastic tube into this, you caninflate the whole of the bottom half of the lung. Be careful when you stop blowinginto the lung as blood and mucus can blow back up the tube!
PitfallsEnsure all pupils are sitting down. Even the toughest pupils have been known tofaint in response to dissection. Some pupils will have quite strong moralobjections to dissection. Some may object on religious grounds to, for example,use of a pig’s or cow’s lungs.
The lungs may be slashed with deep knife cuts by the butcher as part of theprocess of checking for disease in animals.
Safety notesDo not let pupils dissect or touch the lungs without surgical gloves. Wear surgicalgloves yourself, and eye protection. Use thick disposable paper to absorb fluids.Wash the dissection board and sterilise instruments after use.
ICT opportunitiesYou could show pupils an animation from the Internet of the inside of thetrachea.
Search using search terms ‘trachea’ and ‘video’ or use the animation at thefollowing website:
EquipmentFor teacher demonstration:● one set of lungs (with trachea and diaphragm attached)● dissecting board or tray● scalpel● scissors (large and small)● mounted needle● coarse forceps● fine forceps
For your informationRunning the activityOrder a full set of lungs from the butchers at least a week before the class. Tellthem that you want all of the organs intact when you order it. The fresher thelungs, the better they smell!
It is sensible to give squeamish pupils the opportunity not to watch the dissection,and to have something else for them to do, either in another room, or in yourclassroom away from the dissection itself.
During the dissection, outline the structure of the lungs. Include the trachea,bronchi and bronchioles in your discussion, and trace the pathway of air throughall three. Talk about the rings of cartilage on the trachea, and discuss the spongynature of the lungs.
To demonstrate how the lungs inflate, cut into the left lung slightly below theentry point of the left bronchus. There, you will find a branch of the bronchusleading to the lower part of the lung. If you insert a plastic tube into this, you caninflate the whole of the bottom half of the lung. Be careful when you stop blowinginto the lung as blood and mucus can blow back up the tube!
PitfallsEnsure all pupils are sitting down. Even the toughest pupils have been known tofaint in response to dissection. Some pupils will have quite strong moralobjections to dissection. Some may object on religious grounds to, for example,use of a pig’s or cow’s lungs.
The lungs may be slashed with deep knife cuts as part of the process of checkingfor disease in animals.
Safety notesDo not let pupils dissect or touch the lungs without surgical gloves. Wear surgicalgloves yourself, and eye protection. Use thick disposable paper to absorb bodyfluids. Wash the dissection board and sterilise instruments after use.
Running the activityProvide pupils with ICT facilities to write the presentation or leaflet. Also providethem with information sources from which they can research the gas exchangesystems of fish and insects.
Other relevant materialsSkill sheet 4: Web searches
Expected outcomesPupils produce a leaflet or presentation about gas exchange in fish and insects.
ICT opportunitiesPupils could search the Internet for information about gas exchange in fish andinsects.
Pupils produce a presentation or word-processed leaflet of their findings.
Type Purpose DifferentiationDiscussion Pupils learn about how other animals carry out gaseous exchange. Extension
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B3cActivity
ExtensionGas exchange in other animals
If other animals respire, they must have some method wherethey take in oxygen and release carbon dioxide. Some animalshave lungs like us, but in other animals gas exchange happens indifferent ways.
You are going to produce a leaflet or Power Point® presentationto tell other pupils how gas exchange happens in insects and fish.
1 You will need to provide information to answer the followingquestions:What is gas exchange?What organs do insects and fish have instead of lungs?What do these organs look like?How do these organs work?
2 Decide on which Internet search engine you wish to use.
3 Decide on which keywords you are going to use in your search.
4 Start your search, but be selective. Remember you are trying tofind out about how gas exchange happens in insects and fish.
5 Produce a leaflet or presentation based on your findings. Itshould explain your findings in a user-friendly way to someonewho knows nothing about gas exchange in insects and fish.
Tips on producing good leaflets and presentations
● Use colour – it makes it more eye-catching.● Keep it simple – too much detail makes it look untidy and
cluttered.● Stick to a simple message that you want to get across.● Use large diagrams and drawings so that they can be seen from a
Running the activityDraw out the map (including the arrows) onthe floor of your classroom with chalk. Hangup signs to indicate the location of the body,lungs and heart.
Choose one pupil to be the left side of the heart(left heart) and one pupil to be the right side ofthe heart (right heart). Place them in themiddle of the room.
Choose two pupils to be the lungs. Stand themat one end of the room. One will collect bluecards (lung in) and one will pass out red cards(lung out).
Choose two pupils to be the big toe in thebody. One will collect the red cards (toe in) andone will distribute the blue (toe out). Theyshould stand together at the opposite end ofthe room to the lungs.
All remaining pupils will be red blood cells andthey should line up at the lung to receiveoxygen (red cards).
One by one the pupils begin to file past ‘lungout’ and take a red oxygen card.
Once they have their oxygen card, they head for the heart where the left heart pumps them out to the bigtoe. (The left heart just redirects the blood – this could be represented by the pupil playing ‘left heart’holding the hand of each one as they file past.)
At the body, they give their red oxygen cards to toe in, pick up their blue carbon dioxide cards from toeout, and head back to the heart.
This time they file past ‘right heart’ and are guided to the lung.
At the lung, they hand over their blue carbon dioxide cards and pick up more red oxygen cards, and the process begins again.
Other relevant materialFifty sheets of red paper labelled oxygen.Fifty sheets of blue paper labelled carbon dioxide.
PitfallsYou will need to enforce tight classroom management to ensure everyone stays on task and learns from the role-play.
Safety notesWarn pupils not to push and shove during the role-play. Make sure bags and stools cannot cause trips or falls.
Answers1 Individual responses. 2 Red = oxygen; blue = carbon dioxide.3 It is carried to the heart and then the body. 4 It is pumped to the rest of the body.5 It enters the blood and is carried to the lungs 6 respiration
Type Purpose DifferentiationDiscussion Pupils role-play the operation of the circulatory system. Core
B-Teachers(26-36).qxd 29-Sep-03 2:25 PM Page 34
B4aActivity
CoreRound and round
Your heart, body and lungs work together to bring oxygen to allparts of your body. As the oxygen is used up, carbon dioxide isproduced. Your blood carries this waste gas back to the lungswhere you breathe it out.
You are going to use a role play to demonstrate how thishappens.
1 Look at this flow diagram. It shows what happens to blood whenit is pumped around your body.
2 Listen carefully to your teacher. You are going to model the waythe heart, blood and lungs work together.
Write a sentence about what you did and what part of thecirculatory system you represented.What do the red and blue cards represent?What happens to the oxygen that enters the blood in the lungs?What happens to the blood that enters the heart from the lungs?What happens to the carbon dioxide in the big toe?What process is taking place in the big toe that needs oxygenand makes carbon dioxide?
Type Purpose DifferentiationPaper Pupils read a passage of text about red blood cells and how they transport oxygen, and
answer questions.Extension
B-Teachers(26-36).qxd 29-Sep-03 2:25 PM Page 35
B4bActivity
ExtensionTransport for respiration
This activity helps you to work out how the blood carriesthe reactants and products of respiration around the body.
Read the passage below and answer the questions.
In larger organisms like humans, the oxygenand glucose needed for respiration aretransported to the cells by the blood.
● Oxygen travels attached to a specialchemical called haemoglobin inside the red blood cells.
● Glucose is dissolved in the watery part of the blood, called the plasma.
● Oxygen and glucose can pass from the blood to nearby cells where they are needed.
Carbon dioxide and water are the waste products fromrespiration in the body’s cells.
● The water may be used in the cell, or it may pass intothe blood to be taken away.
● Carbon dioxide is always taken away dissolved in the blood.
Arteries carry blood away from the heart and veins carry blood back towards the heart.Capillaries connect up the arteries and veins. The walls of a capillary are made of just asingle layer of cells. This allows oxygen and carbon dioxide topass through easily for respiration.
The capillaries are not the only things well adapted to theirjob. The red blood cells are also good at carrying oxygenaround the body. Because of their shape, they can fit in a lot of haemoglobin. They are also flexible and can bend alittle to squeeze down the narrowest capillaries.
1 Which part of the blood carries water around the body?2 Which type of blood cell carries oxygen around the body?3 What is the name of the chemical inside the cell that the
oxygen is attached to?4 What is the function of a arteries and b veins?5 Explain what ‘well adapted’ means.6 What is the function of capillaries? Describe why they are well adapted for that
function.7 Write down two ways in which red blood cells are well adapted for carrying oxygen
Running the activityDemonstrate the experiments carried out by the characters in the Pupil bookspread, pages 22–23, and develop the hypotheses and predictions developed bythe book characters. Begin by showing pupils fermenting yeast, and explain that ithas been on top of the radiator. Outline Ryan’s hypothesis and ask pupils tosuggest something that would happen if Ryan’s hypothesis were correct.
Focus on the prediction from the Pupil book spread that the beaker will bubblefaster if you heat it up. Heat the fermenting yeast over a Bunsen burner, andobserve that the bubbles initially increase, and then observe the solution stopbubbling altogether.
Ask pupils to decide if their hypothesis was correct, and then tell them that yeastis a living organism. Ask them to suggest their own hypothesis now to account fortheir results, reminding them of what they know about respiration.
Expected outcomesPupils see a demonstration of the experiment carried out in the Pupil book to helpthem understand the thought processes involved in hypothesising, predicting andusing evidence.
PitfallsYeast can sometimes be unpredictable. Make sure that you have the yeast bubblingbefore the lesson so you do not need to spend time warming it up at thebeginning.
Safety notesKeep pupils at a safe distance when heating the yeast. Ensure no one ingests any ofthe yeast.
Type Purpose DifferentiationPractical Demonstration to show pupils what the characters in the Pupil book spread carried out. No pupil sheet
B-Teachers(26-36).qxd 29-Sep-03 2:25 PM Page 36
B5aTechnician
activity notesIs yeast a chemical?
EquipmentFor teacher demonstration:● 15g baker’s yeast mixed with 300ml water and 300ml 0.2M glucose solution
(leave on a radiator for 20minutes to start bubbling before the lesson)● 500ml beaker● Bunsen burner● tripod● heatproof mat● gauze
For your informationRunning the activityDemonstrate the experiments carried out by the characters in the Pupil bookspread, pages 22–23, and develop the hypotheses and predictions developed bythe book characters. Begin by showing pupils fermenting yeast, and explain that ithas been on top of the radiator. Outline Ryan’s hypothesis and ask pupils tosuggest something that would happen if Ryan’s hypothesis were correct.
Focus on the prediction from the Pupil book spread that the beaker will bubblefaster if you heat it up. Heat the fermenting yeast over a Bunsen burner, andobserve that the bubbles initially increase, and then observe the solution stopbubbling altogether.
Ask pupils to decide if their hypothesis was correct, and then tell them that yeastis a living organism. Ask them to suggest their own hypothesis now to account fortheir results, reminding them of what they know about respiration.
Expected outcomesPupils see a demonstration of the experiment carried out in the Pupil book to helpthem understand the thought processes involved in hypothesising, predicting andusing evidence.
PitfallsYeast can sometimes be unpredictable. Make sure that you have the yeast bubblingbefore the lesson so you do not need to spend time warming it up at thebeginning.
Safety notesKeep pupils at a safe distance when heating the yeast. Ensure no one ingests any ofthe yeast.
Review learning● Make flashcards from the pupil sheet, showing the names of
the reactants and products of respiration.
● Hand out each flashcard to different pupils. Ask these pupilsto hold up their cards then, as a class, decide which order thecards should go in to produce the equation for respiration.
Sharing responses● As a class, share and discuss each group’s predictions, results
and conclusions for Activity B1c.
Group feedback● Pupils present their Power Point® presentations from Activity
B1a.
Word game● Ask pupils to play Snap! in pairs, using the cards on the pupil
sheet.
Looking ahead● Ask pupils to write a short poem about respiration using these
Review learning● Pupils play a game of word bingo.
● Pupils select nine words from the list to write into their bingogrid.
● Read out definitions from the teacher sheet in any order. Pupilsmatch these to their chosen words. The game is over when apupil can strike out a line.
● The ‘winning’ pupil has to recall the definitions of the words asthey read each one in the winning line to the class.
Sharing responses● Share feedback and conclusions from Activity B2a.
● Conclude that plants appear to respire in the same way ashumans.
Group feedback● Ask those groups of pupils who have carried out Activity B2b to
discuss their results.
● They should try to explain why particular tissues in the plantmay need more energy than others, and why the speed ofrespiration may therefore be different between the differentparts of the plant.
● After three minutes, send one member of each group over to adifferent group. Once there, they should explain their group’sideas, and listen to the ideas from this new group.
● On return to their original group, they should use the othergroup’s ideas to help refine their own ideas.
● Each group should produce an OHT summarising their ideas.
Word game● Pupils work in pairs and place all the cards face down.
● They take it in turns to turn over two cards and look at thembefore turning them face down again. They need to rememberwhere the cards are so that they can turn up a pair of cards sothe word on one of the cards fills the gap in the phrase on theother.
● The person with the most correct pairs wins.
Looking ahead● Give pupils the list of answers on the board. Ask them to work
in pairs to devise a question that would result in each of theseanswers.
Plants make their own food using air,water and energy.
light
An indicator turns ifcarbon dioxide is produced.
yellow
All living things . respire
You can tell if something respiresbecause it often releases
energy.heat
Plants can die in waterlogged soil,because their roots do not get enough
.oxygen
B-Plenaries(45-57).qxd 29-Sep-03 2:26 PM Page 51
B3 PlenariesBreathe in and out
Review learning● Play ‘What happens next?’ to describe the passage of air into the
lungs. Begin by saying ‘Air enters the mouth. What happensnext?’, and then to each response reply ‘What happens next?’until you reach gaseous exchange in the alveolus.
Sharing responses● As a class, pool conclusions from the four experiments A–D from
Activity B3a.
● Repeat the experiments at the front, if necessary, so that allpupils see all experiments.
Group feedback● Share ideas and research from Activity B3c.
● Ask pupils to summarise the whole group’s findings by writingdown the special features each living thing has to carry outgaseous exchange.
● By taking contributions from each group, make a list ofrequirements for any gaseous exchange system.
Word game● Give each pupil a card containing a question and an answer. Ask
one pupil to stand up and read out the question on their card,then sit down. The pupil who has an appropriate answer to thisquestion stands up, reads out their answer, then asks thequestion on their card and sits down, and so on. The game iscomplete when the pupil who started the game stands up for asecond time to read out the answer on their card. The loop iscomplete. If there are not enough question/answer cards for thewhole class, you may need to make extra copies. Some pupilswill have the same question/answer card – the first one to standup gets to read their answer and ask their question.
● Before cutting up the pupil sheet, copy and reorder it so that youhold a copy of the correct answers next to their respectivequestions.
Looking ahead● Read out the statements about the heart on the teacher sheet
and ask pupils to decide if the statements are true or false. Makeit clear that pupils may not know all the answers yet, but theywill find them in the next lesson.
2 It takes 20minutes for blood to flow around your body and back to the heart. F
3 Most people measure their pulse in their ankle. F
4 Your heart beats less quickly when you exercise. F
5 The heart is found in the chest. T
6 Blood is carried through the body in tubes. T
7 Capillaries carry blood through the organs of the body. T
8 An artery carries blood towards the heart. F
B-Plenaries(45-57).qxd 29-Sep-03 2:26 PM Page 54
B4 PlenariesA transport system
Review learning● Show pupils the slideshow about the effects of smoking
on the lungs.
● Ask them to write down ways emphysema stops the lungsdoing their job properly.
Sharing responses● Ask pupils questions as a whole class to make learning
explicit from the circulation game in Activity B4a.
● Check pupils understand what each part of the modelrepresents.
● Ask pupils if they think the model is a good one.
● Ask pupils to suggest ways in which this model of thecirculatory system could be improved.
Group feedback● In groups, pupils check their answers from the reading
exercise in Activity B4b.
Word game● Ask pupils to write a set of directions for the blood to
navigate around the circulation.
● Put the task in the context of a delivery driver picking upand dropping things off on the way (e.g. turn right in theventricle and increase in speed up to the aorta).
Looking back● Pupils revise and consolidate knowledge from the unit.
● They can use the Unit map, Pupil checklist, or the Testyourself questions.
1 Draw lines to join the labels to the diagram of your lungs.
2 These sentences describe how oxygen gets into your blood.They’re all mixed up! Write numbers in the boxes toput them in order.
lungs
ribs
diaphragm
heart
nose
mouth
windpipe
The air I breathe in goes into tiny air sacs called alveoli.Oxygen from the air goes through the thin walls of thealveoli into my blood.
The oxygen goes from my blood into my cells. The cellsuse the oxygen to get energy from my food. They makecarbon dioxide which they need to get rid of.
When I breathe in, air goes into my lungs.
My blood carries the oxygen to every cell in my body.
bronchi
B-Specials.qxd 29-Sep-03 1:10 PM Page 5
B3 SpecialsBreathe in and out (continued)
3 Write true or false for each sentence.
a My lungs put carbon dioxide gas into my blood.
My lungs also take oxygen gas from my blood and
put it into the air inside them.
b Gas exchange is when oxygen goes into my blood
and carbon dioxide goes out of my blood.
c Alveoli are tiny air sacs with thick walls.
4 The carbon dioxide made when your cells respireneeds to be removed.Use words from this list to fill the gaps. You can useeach word once, more than once, or not at all.
2 a Correct labels from left to right – nucleus,cytoplasm, cell membrane
b Release energy to be used in the body.c i glucose, oxygen
ii water, carbon dioxide
3 My body gets glucose from … the food I eat.My body gets oxygen from … the air I breathein.I get rid of water in … the air I breathe out.I get rid of carbon dioxide in … the air I breatheout.
4 a musclesb hotc heart, glucosed breathing, oxygen
B2 Everything respires1 a Coloured red – glucose
b Coloured yellow – water, carbon dioxide,light energy
c Coloured blue – water, carbon dioxide
2 leaf
3 a redb yellowc Carbon dioxide.d The living things respiring.e Both plants and animals respire.
B3 Breathe in and out1 Correct labels anticlockwise from top left – nose,
4 a carbon dioxide, bloodb lungsc blood, aird breathe out.
5 a i ✗ii ✓
iii ✓iv ✗v ✓
vi ✓vii ✗
b i There is more oxygen in the air than carbon dioxide or There is lesscarbon dioxide in the air than oxygen.
iv I breathe out less oxygen than I breathein.
vii My cells use oxygen to release the energyfrom my food.
B4 A transport system1 blood – The transport system of the body.
heart – This pumps blood around the body.arteries – These tubes take blood away from theheart.veins – These tubes carry blood back to theheart.left side of heart – This pumps blood to thelungs.right side of heart – The muscle that pumpsblood around the body.capillaries – The tiny tubes that connect arteriesto veins.
2 a trueb truec falsed false
3 a Clockwise from the top – lungs, vein, carbon dioxide, carbon dioxide, vein,capillary, artery, oxygen, oxygen, capillaryIn the middle the label is heart.
b to e Correct colours.
B5 Trouble with yeast1 2, 4, 3, 1.2 Ticks next to b, d and e.3 Tick next to b.
1 Bronwen is running a marathon. Copy and complete these sentencesabout Bronwen’s body, by choosing from the words below.
When she is running, Bronwen’s leg needs lots
of energy. The energy comes from and
in her blood. Her muscle cells are . Bronwen’s heart
is beating and she is deeply to get
enough oxygen and glucose to her muscle . Bronwen is
sweating because some of the energy is released as .
2 Copy and complete the mind map below. Use only the words in the list.
1.
2.
3.
forthe
body
is likea
is transferredto heat and movement in
CHEMICAL ENERGYIN FOOD
comesmostlyfrom
4. and
by
and6.
5. repairing
7.
is used
for..........................
.............................
....................................
........................................
........................................
...................................
...............................
heat fast cells
joints air
muscles glucose
water
oxygenbreathing
respiring
fuel cells
fat
growth
respiration
musclescarbohydrate
B-Homework.qxd 22-Oct-03 3:09 PM Page 1
B1 HomeworkFood for energy (continued)
CORE
3 Omar has been cycling fast for an hour. Explain why his legs arereally aching but his arms are not.
4 In an exercise class Fatima is working harder than Morag. Copyand complete the statements below to write five correctsentences comparing Fatima and Morag.
a Fatima’s breathing will probably be …
b Morag will probably be sweating …
c Fatima’s muscles will probably be aching …
d Morag’s heart will probably be beating …
e Fatima will probably be respiring …
EXTENSION
5 a Write down the word equation for the respiration of glucose.
b The word equation for burning glucose is identical to the onefor respiring glucose.
Imagine that dragons really existed. Give two reasons why adragon’s fire could not be caused by respiration.
6 a Explain two ways in which anaerobic respiration in humans isdifferent from aerobic respiration.
b Why does anaerobic respiration make muscles tired andaching?
c Yeast respires anaerobically.i What is the name of this process in yeast?ii Why is it more useful than anaerobic respiration in
1 a Copy this diagram of a plant cell then label it, using the words below.
b Name the process happening in the cell.
c Copy and complete the following sentence:
Respiration is very important for plants and animals because …
CORE
2 Dr Lo has a pet snake. He keeps it in a glass tank. There is a smallgap between the glass lid and the top of the tank.
a Explain why it is important to have a gap between the lid and the tank.
b If there was no air gap:i what would happen to the amount of oxygen in the tank?ii what would happen to the amount of carbon dioxide in the tank?iii what would happen to the amount of water vapour in the tank?
c Dr Lo bubbled some of the air, from inside the tank without an air gap,through red hydrogencarbonate indicator.i What happened to the colour of the indicator?ii Why did this happen?
d i What should Dr Lo also test, to be sure that the indicatorchanged because of something inside the tank?
ii What do scientists call this type of extra test?
3 a Explain why dormice only breathe around ten times everyminute, during hibernation, compared with over 100 breathsper minute when awake.
b Describe, with reasons, what probably happens to the bodytemperature of dormice during hibernation compared withwhen they are awake.
c Explain why a shortage of food during summer and autumnmight mean that many dormice die during the winter.
4 In 1774, a British scientist called Joseph Priestley used mice toinvestigate air. He put a mouse into a sealed jar and timed howlong it took to collapse through lack of oxygen.
a Imagine that Priestley had used two different mice. One waswide-awake and the other was hibernating.i Which mouse would collapse first?ii Why would it collapse first?
b Explain, with reasons, whether or not it would be possible tocarry out Priestley’s experiments today.
4 Gemma is giving mouth-to-mouth resuscitation to a casualty. Shebreathes her exhaled air into the casualty’s lungs.
a Explain why Gemma’s exhaled air can keep the casualty’s cellsrespiring.
b Why is it very important that, after every breath, Gemma liftsher face and takes a breath of fresh air?
c Plastic bags often carry a warning to keep them away fromyoung children. Why might a person die, if they put theirhead inside a plastic bag and took several breaths?
5 Jenny suffers from an inherited disease called cystic fibrosis. Thiscauses a build up of thick mucus inside her alveoli. Explain whythis makes breathing difficult for Jenny.
b Copy and complete these sentences, using only the words oxygenor carbon dioxide.
i Arteries contain more than veins.
ii Veins contain less than arteries.
iii When blood comes out of a muscle it contains more
than when it went into the muscle.
c i The heart and blood vessels form part of a body system.Name the system.
ii Which other part of your body belongs to this system?
CORE
2 a At point A on the diagram, where is theblood going to next?
b i Which important gas is in the blood atpoint B?
ii Where has this blood just come from?
c Why is the wall of the heart at point Cthicker than it is at point D?
d i Is the blood vessel at point E an artery or a vein?ii Explain how you worked out your answer.
3 When Paula is running her heart beats over twice as many times perminute as when she is resting.
a How does this:i affect the speed at which Paula’s blood travels round her body?ii affect the amount of oxygen that reaches Paula’s muscles every minute?
b Paula’s breathing rate also changes, when she is running.How and why must her breathing rate change?
c After the race, why does Paula’s heart rate slow down?
Type of blood vessel Function (job) of the blood vessel
Vein
Capillary
Artery
D
valves
artery
E
B
C
A From thelungs
wall
vein
B-Homework.qxd 22-Oct-03 3:10 PM Page 8
B4 HomeworkA transport system (continued)
EXTENSION
4 Look at the diagram below. It shows a ‘cut-away’ blood vessel.
a i Is the vessel an artery or a vein?ii Explain how you could tell.
b How did William Harvey use the information, shown in thediagram, to explain how blood circulation works?
5 The Roman doctor Galen thought that blood leaked through tinyholes between the left and right sides of the heart. It is possible,though rare, to be born with a ‘hole in the heart’, so that blooddoes leak from one side into the other. Chloe has a hole in herheart. Explain why this would make it hard for her to take part insport.
1 Correct sequence is: muscles, oxygen, glucose (or glucose, oxygen), 8respiring, fast, breathing, cells, heat. Award 1 mark for each correctword.
2 1 fuel, 2 muscles, 3 respiration, 4 growth, 5 cells, 6 carbohydrate, 7 fat. 7Award 1 mark for each correct entry as numbered above.
Total for Help 15
COREQuestion Answer Mark
3 Omar’s leg muscles are working hard 1Omar cannot get enough oxygen to his leg muscles 1his legs are respiring without oxygen and are doing anaerobic respiration 1Omar’s arms are not working hard 1so never need to respire without oxygen or do anaerobic respiration. 1Accept equivalent statements for each marking point.
4 a Fatima’s breathing will probably be faster than Morag’s. 1
b Morag will probably be sweating less than Fatima. 1
c Fatima’s muscles will probably be aching more than Morag’s. 1
d Morag’s heart will probably be beating more slowly than Fatima’s. 1
e Fatima will probably be respiring faster than Morag. 1
Total for Core 10
EXTENSIONQuestion Answer Mark
5 a Glucose + oxygen → carbon dioxide + water Accept glucose and oxygen reversed 1and carbon dioxide and water reversed.
b Respiration is slow and controlled 1respiration happens at a much lower temperature than burning. 1
6 a It does not require oxygen 1It produces lactic acid. 1
b Lactic acid is poisonous. 1
c i Fermentation 1
ii Makes ethanol/alcohol. 1Makes bread/dough rise. 1
1 Matching sentences are:During breathing my chest moves up and down because air is 1moving in and out of my lungs.Tiny animals do not need lungs because gases can pass straight 1into them from the air.I breathe out a lot of carbon dioxide because respiration in my 1cells makes it as a waste product.Gases can move easily through the walls of my alveoli because 1they are very thin.Gas exchange in my lungs is very important because it provides 1the oxygen I needed for respiration and removes waste gases.
Total for Help 5
COREQuestion Answer Mark
2 The sequence of labels clockwise from top left is: windpipe, 6nose, mouth, lung, heart, ribAward 1 mark for each correctly positioned label.
3 a The label sequence, from top left clockwise is: exhaled air 1oxygen 1carbon dioxide. 1
b (Tiny) blood vessels. 1
c Air breathed out contains:less oxygen 1more carbon dioxide than air breathed in. 1
Total for Core 12
EXTENSIONQuestion Answer Mark
4 a Exhaled air still contains oxygen 1so this can be absorbed into the casualty’s bloodstream. 1
b To make sure that the amount of oxygen breathed into the casualty is as 1high as possible.
c Oxygen is removed quickly, after three or four breaths 1carbon dioxide quickly increases 1casualty would suffocate. Accept equivalent answers. 1
5 Smaller surface area for gas exchange. Accept equivalent answers. 1
1 a Vein – carries blood away from an organ. 1Capillary – connects arteries and veins or carry blood through organs and tissues. 1Artery – carries blood towards an organ. 1
b i Oxygen 1
ii Oxygen 1
iii Carbon dioxide 1
c i Circulatory system 1
ii Blood 1
Total for Help 8
COREQuestion Answer Mark
2 a To the lungs. 1
b i Oxygen 1
ii From the lungs. 1
c So that it can pump blood right round the body. 1
d i A vein. 1
ii It is coming from the organs to the heart. Accept equivalent answers. 1
3 a i Travels faster. 1
ii Increases it. 1
b Increase/gets faster/more breaths per minute. 1
c Muscles no longer need so much oxygen 1so blood does not have to travel so fast to get it to them. 1 Accept equivalent answers.
Total for Core 11
EXTENSIONQuestion Answer Mark
4 a i Vein 1
ii It has valves. 1
b Valves mean blood cannot flow backwards 1so it could only go into the heart through veins, not out 1so it must flow in a circle round the system. Accept equivalent answers. 1
5 Not all the blood goes through Chloe’s lungs so her blood gets less oxygen 4than it should so her muscles cannot respire as fast. Chloe gets out of breathvery quickly. Or a similar argument based on oxygenated blood from the left side ofher heart leaking into the right side and never getting round her body.Quality of written communication is good. 1
Total for Extension 10
B-Homework.qxd 22-Oct-03 3:10 PM Page 13
B Test yourselfRespiration
1 Complete these sentences about respiration by crossing out the wrongwords.
a Oxygen is produced/used up in respiration.
b Glucose is used up/produced in respiration.
c Carbon dioxide is produced/used up in respiration.
d Water is produced/used up in respiration.
e The purpose of respiration is to produce energy/food/oxygen.
f Respiration is a chemical reaction that happens in all cells/only insome cells.
g Only animals/only plants/all living things respire.
2 Draw lines to join up the sentences to explain the changes in the bodywhen there is not enough oxygen.
We breathe faster … ●●
… the blood cannot supply enough oxygen for the cells’ needs.
During intense ●
… because respiration is physical activity … ● happening at a faster rate and more
heat is given off.
We feel hotter … ●●
… in order to take in oxygen more quickly.
3 Which of these are true about both plants and animals? Underline thetrue statements.
4 Complete these sentences by crossing out the wrong words.
a Oxygen enters the blood in the lungs/body cells.
b Carbon dioxide enters the blood in the lungs/body cells.
c Oxygen leaves the blood in the lungs/body cells.
d Carbon dioxide leaves the blood in the lungs/body cells.
e There is more/less carbon dioxide in the air we breathe outthan in the air we breathe in.
5 During gas exchange in the lungs, oxygen moves into thebloodstream and carbon dioxide moves out. Alveoli have specialfeatures so gas exchange happens easily.Draw lines to match each features with the reason it helps gasexchange.
Feature Reason for feature
thin walls ●●
a lot of gas can pass into the blood at once
network of blood ● ●
easy for gases to pass capillaries through
large surface area ● ●gases can easily pass into the blood
6 Put these statements in the correct order, starting with letter D.
A The blood also collects glucose from the digestive system.
B Blood containing oxygen goes back to the heart.
C The blood collects carbon dioxide from the cells.
D From the heart, blood goes to the lungs to collect oxygen.
E The heart pumps blood to the body.
F From the heart, blood returns to the lungs.
G The blood with carbon dioxide goes through the heart.
H The blood delivers oxygen and glucose to the cells.
4 Complete these sentences by crossing out the wrong words.
a Oxygen enters the blood in the lungs/body cells.
b Carbon dioxide enters the blood in the lungs/body cells.
c Oxygen leaves the blood in the lungs/body cells.
d Carbon dioxide leaves the blood in the lungs/body cells.
e There is more/less carbon dioxide in the air we breathe outthan in the air we breathe in.
5 During gas exchange in the lungs, oxygen moves into thebloodstream and carbon dioxide moves out. Alveoli have specialfeatures so gas exchange happens easily.Draw lines to match each features with the reason it helps gasexchange.
Feature Reason for feature
thin walls ●●
a lot of gas can pass into the blood at once
network of blood ● ●
easy for gases to pass capillaries through
large surface area ● ●gases can easily pass into the blood
6 Put these statements in the correct order, starting with letter D.
A The blood also collects glucose from the digestive system.
B Blood containing oxygen goes back to the heart.
C The blood collects carbon dioxide from the cells.
D From the heart, blood goes to the lungs to collect oxygen.
E The heart pumps blood to the body.
F From the heart, blood returns to the lungs.
G The blood with carbon dioxide goes through the heart.
H The blood delivers oxygen and glucose to the cells.
1 a When you run fast these are changes in the way you breathe and in the way your heart beats. Describe both these changes. 2 marks
b The air that you breathe in is different from the air that you breathe out in several ways.Copy and complete the table below to show four differences. 4 marks
c Explain the reason for one of the differences you have given. 1 mark
2 The picture shows a part of the human body. Two organs are labelled X and Y.
a Write the names of the organs X and Y. 2 marks
b The organs and organ systems have different functions. In which organ is oxygen absorbed into the blood? 1 mark
c Give the function of the circulatory system. 1 mark
d What part does the heart play in the circulatory system? 1 mark
e What would happen in the cells if they were not supplied with enough oxygen? 1 mark
Inhaled air (breathed in) Exhaled air (breathed out)
more oxygen
more water vapour
cooler warmer
A-C-EUTest.qxd 25-Nov-03 8:41 AM Page 7
BEnd of unit test
GreenRespiration (continued)
3 Both the rabbit and the dandelion have to respire.Aerobic respiration takes place in all their cells.
a Which gas do they both need for aerobic respiration? 1 mark
b Write down three things released in their cells by respiration. 3 marks
c Why do all living things need to respire? 1 mark
4 Why do all the cells in the body need a good blood supply? Give two reasons. 2 marks
5 We know today that blood circulates around the body through arteries, capillaries and veins.
In ancient times, the only evidence for circulation came from dissecting dead bodies. Arteries were usually found to be empty.
a Aristotle had a theory that air passed through the arteries. What evidence did he have for this? 1 mark
b We now know that many old ideas about circulation of the blood were wrong. What are modern scientific ideas based on? 1 mark
Measuring your pulse tells you how many times your heart beats in one minute. You count how many times you feel your pulse in one minute. Kate and her class measured their pulse rate.
c What should Kate do to check her results from taking her own pulse are reliable? 1 mark
Some teenagers have much faster pulse rates than others. Their rates slow down as they go through puberty.
d What could Kate do to see if any of her class were like this? 1 mark
e What should Kate and her class do to check how their pulse rate changes? 1 mark
1 The picture shows a part of the human body.Two organs are labelled.
a The organs and organ systems have different functions.Write the name of the organ where oxygen is absorbed into the blood. 1 mark
b Give the function of the circulatory system. 1 mark
2 Both the rabbit and the dandelion have to respire.Aerobic respiration takes place in all their cells.
a Which gas do they both need for aerobic respiration? 1 mark
b Why do all living things need to respire? 1 mark
3 What would happen in the cells of the body if they were not supplied with enough oxygen? 1 mark
4 Why do all the cells in the body need a good blood supply? Give two reasons. 2 marks
5 Some students carried out an experiment to see how their breathingrate, pulse rate and skin temperature changed as they carried outvarious activities. Pulse rate is the number of times your heart beatsper minute. Their results are shown in the table below.
a The breathing rate increases during physical activity. Give one reason for this. 1 mark
b The pulse rate increases too during physical activity. Give one reason for this. 1 mark
c Explain the change in skin temperature after exercise. 1 mark
Activity Breathing rate Pulse rate Skin temperature (breaths per minute) (beats per minute) (°C)
sitting 16 70 33
walking 20 84 34
cycling 32 130 35
running 54 150 36
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BEnd of unit test
RedRespiration (continued)
6 Kirsty used the apparatus shown below to collect a sample of exhaled air.
a There are differences in composition between the air that Kirsty breathed in and the air that she breathed out. Copy and complete these sentences, choosing the correct word from each pair. 2 marksi Inhaled air contains more/less oxygen than exhaled air.ii Inhaled air contains more/less carbon dioxide than
exhaled air.
b Explain the reasons for the two differences. 2 marks
Kirsty then used her sample of exhaled air in the experiment shown in the diagram.
c Candle X will burn for longer than candle Y. Explain why. 1 mark
d Give one way in which burning and respiration are the same. 1 mark
e Write a word equation for the chemical reaction that takesplace in respiration. 2 marks
7 The alveoli are the parts of the lungs where gaseous exchange takes place.
a Below are three features of the alveoli which help in gaseous exchange.
Choose one feature and explain how it helps in gaseous exchange. 1 mark
b Explain why damage to alveoli results in less gaseous exchange. 1 mark
8 Measuring your pulse tells you how many times your heart beatsin one minute. You count how many times you feel your pulse inone minute. Kate and her class measured their pulse rate.
a What should Kate do to check her results from taking her own pulse are reliable? 1 mark
Some teenagers have much faster pulse rates than others. Their rates slow down as they go through puberty.
b What could Kate do to see if any of her class were like this? 1 mark
c What should Kate and her class do to check how their pulse rate changes? 1 mark
In ancient times, the only evidence for circulation came from dissecting dead bodies. Arteries were usually found to be empty. Aristotle had a theory that air passed through the arteries.
d In 1628, William Harvey showed that blood flowed through the arteries. What did this evidence do to Aristotle’s theory? 1 mark
e It was not until the invention of the microsocpe that the puzzle about the circulation was finally solved. Why was the microscope needed to solve the puzzle? 1 mark
Less oxygen (in exhaled air) or more oxygen (in inhaled air) because oxygen is used up in respiration.More carbon dioxide (in exhaled air) or less carbon dioxide (in inhaled air) because carbon dioxide is produced in respiration.More water vapour (in exhaled air) because water is produced in respiration.
2 a X=heart. 1 4
Y=lungs or lung. 1 4
b Lungs 1 5
c To transport substances (around the body). 1 5(Accept transport of a named substance, e.g. oxygen, glucose, carbon dioxide.)
d Pumps blood (around the body). 1 5
e The cells would not be able to respire enough to release all the energy they need. 1 5
3 a Oxygen 1 5
b Carbon dioxide 1 6
Water 1 6
Energy 1 6
c To get energy from food or to produce or release energy 1 5
4 All cells respire so they need to receive the raw materials oxygen and glucose 1 5and have waste materials such as carbon dioxide removed. 1 5
5 a Arteries were usually found to be empty. 1 4
b Evidence 1 4
c Repeat the experiment. 1 5
d Collect class results and look for patterns. 1 5
b To transport substances (around the body). (Accept transport of a named substance, e.g. oxygen, glucose carbon dioxide.) 1 5
2 a Oxygen 1 5
b To get energy from food or to produce or release energy. 1 5
3 The cells would not be able to respire enough to release all the energy they need. 1 5
4 All cells respire so they need to receive the raw materials oxygen and glucose 1 5and have waste materials such as carbon dioxide removed. 1 5
5 a Any one from: 1 5To take in more oxygen. To get rid of more carbon dioxide.
b Any one from: 1 6To supply cells with oxygen more quickly. To supply cells withglucose more quickly. To carry away carbon dioxide more quickly.
c Respiration gives out heat energy. 1 6
6 a i Inhaled contains more oxygen than exhaled air. 1 4ii Inhaled air contains less carbon dioxide than exhaled air. 1 4
b Because oxygen is used up in respiration. 1 5Because carbon dioxide is produced in respiration. 1 5
c Inhaled air (or air around candle X) contains less carbon dioxide or more oxygen than exhaled air (or air around candle Y). 1 6
d Any one from: 1 6They give out energy or carbon dioxide or water.They use oxygen.
e glucose + oxygen → carbon dioxide + water + energy (One mark for reactants, one for products.) 2 7
7 a Any one from: 1 6Thin walls: oxygen and carbon dioxide can pass easily through the walls into and out of blood.Good blood supply: oxygen is carried away from the lungs quickly or carbon dioxide arrives at the lungs quickly.Moist lining: gases can dissolve in water (before passing through walls).
b Damaged alveoli have a smaller surface area (for gas exchange). 1 6
8 a Repeat the experiment. 1 5
b Collect class results and look for patterns. 1 5
c Take pulse before and after exercise. 1 5
d Disproved it. 1 6
e Capillaries are very small/could only be seen with a microscope. 1 6
3 The glucose provides them with an instantsource of energy by respiration.
Reda Reactants are glucose and oxygen. Products are
carbon dioxide, water and energy.b When your body can’t supply enough oxygen to
your cells.1 It is necessary to provide energy for the
organism to continue to live.2 Oxygen is used to ‘burn’ a substance to
produce energy. With wood, carbon dioxide,water and heat/light energy are produced. Inrespiration, glucose is ‘burned’ to producecarbon dioxide, water and energy for the cellsto live.
3 The room full of people has more carbondioxide and less oxygen than the room withonly one person.
4 Aerobic respiration uses oxygen from our lungsto react with glucose to produce energy, alongwith water and carbon dioxide. Anaerobicrespiration produces energy from glucose alone,producing energy and lactic acid; this processcan only continue for a relatively short time.
5 It is used to make alcohol (ethanol).
B2 Everything respiresGreena In all plant cells.b From the air and water by using sunlight.c That the seeds did respire.d As a fair test or as a control.e The maggots respired and gave out carbon
dioxide.1 Plants and animals release energy from food.
This process is called respiration. It takes placein all living cells.
2 oxygen3 Enclose the cells in a container at the bottom of
which is an indicator for carbon dioxide.
Reda In all plant cells.b That the seeds did respire.c As a fair test or as a control.d Both the plant root and maggots respired, giving
out carbon dioxide.e i To act as a fair test or control.
ii So that heat energy would not betransferred from or to the room.
iii The maggots. The temperature change wasthe greatest.
iv Individual answers. (They could haveextended the time of the experiment or thenumber of experimental set-ups used.)
v No. Many identical experiments should beset up. The more experimental resultsrecorded, the more accurate the finalaveraged result will be.
1 a oxygenb Carbon dioxide.
2 If the soil is waterlogged the roots cells cannotget enough oxygen for respiration and the plantwill die.
3 Put the respiring cells into a container at thebottom of which is some hydrogencarbonateindicator. If the cells are respiring the carbondioxide will turn the indicator from red to yellow.
B3 Breathe in and outGreena From the air.b The air breathed in has more oxygen and less
carbon dioxide than the air breathed out. This isbecause the oxygen in the air breathed in is usedfor respiration in the cells. During respirationcarbon dioxide is produced. So when the air isbreathed out it has less oxygen and more carbondioxide.
c i oxygenii Carbon dioxide.
d Carbon dioxide.1 Individual answers.
Reda From the air.b The air breathed in has more oxygen and less
carbon dioxide than the air breathed out. This isbecause the oxygen in the air breathed in is usedfor respiration in the cells. During respirationcarbon dioxide is produced. So when the air isbreathed out it has less oxygen and more carbondioxide. Water vapour is higher in the air webreathe out because water is formed as a productof respiration. The amount of nitrogen is thesame in both the air breathed in and out becausenitrogen is neither used nor produced in the cells.
1 a The movement of gases in the alveoli iscalled ‘gas exchange’.
b Nitrogen does not enter into any reactions inthe cells and no nitrogen is produced in thecells, so the amount we breathe in is exactlythe same as that we breathe out.
2 Billy is incorrect because although there is morecarbon dioxide in the air we breathe out, it isnot mainly carbon dioxide. In fact, the air webreathe in is mainly nitrogen, as is the air webreathe out. The air breathed in has moreoxygen and less carbon dioxide than the airbreathed out. This is because the oxygen in theair breathed in is used for respiration in thecells. During respiration carbon dioxide isproduced. So when the air is breathed out it hasless oxygen and more carbon dioxide.
3 Being short of breath – finding it difficult to getenough air to breathe comfortably. This occursbecause the alveoli are clogged up and cannotprovide the gas exchange needed to get oxygenand for normal respiration.
4 Oxygen enters body via lungs, oxygen enters thealveoli, oxygen enters blood, oxygen passes intocell, cell uses oxygen to respire and producecarbon dioxide, carbon dioxide passes from cellinto blood, carbon dioxide passes from bloodinto alveoli, carbon dioxide enters lungs, carbondioxide leaves body via lungs.
B4 A transport systemGreena Individual work.b twicec From experimentation on live animals, Harvey
showed that blood flowed out of the heartthrough arteries and came back through theveins.
d He explained that arteries and veins wereconnected by lots of tiny blood vessels orcapillaries. The blood could then go round in acircle. Valves in the blood vessels stop the bloodflowing backwards.
1 The left side of the heart pumps blood from thelungs to the body. The right side pumps bloodfrom the body back up to the lungs.
2 Individual answers.3 Individual answers.
Reda The valves allow the blood to flow one way only.b The blood pressure in the arteries is very high.
c
1 The circulatory system transports reactants andproducts of respiration to and from all cells inthe body. The blood collects oxygen from thelungs and glucose from the digestive system anddelivers them to the cells.
2 The blood passes through the heart twice forevery time it completes a single circuit.
3
4 Individual answers.5 Appropriate drawing of time line with
markings at:Aristotle (~350 BC ) – Arteries are full of air.Roman times (~50 BC ) – Doctor Galen suggestedblood pumped through arteries; blood got intoarteries by leaking through tiny holes in the wallseparating left and right sides of heart.
Idea Support
Arteries are full of air. Arteries were empty indead bodies.
Blood pumped Roman doctor’sthrough arteries. suggestion.
Blood leaked through Roman doctor’stiny holes in wall suggestion. separating left and right sides of heart.
No holes in wall Dissection of hearts of heart. from dead bodies by
Versalius.
Blood flows out of Harvey’s experiments heart through on live animals. arteries and backthrough veins.
Human veins have Harvey’s experimentsone-way valves. on live animals.
Arteries and veins Harvey’s suggestion.connected by capillaries.
AD 1543 – Versalius showed no such holes bydissecting dead bodies.AD 1628 – William Harvey experimented on liveanimals: showed that blood flowed out of heartthrough arteries and came back through veins;veins have one-way valves; suggested arteriesand veins connected through capillaries soblood could go round in circle.End of seventeenth century – After microscopeinvented Malpighi saw capillaries, provingHarvey correct.
B5 Trouble with yeastGreena That yeast is a chemical which reacts with sugar
to make a gas.b That the reaction would go faster if they heat
the mixture.c There was a reaction which gave off a gas.d After they boiled the mixture the mixture
stopped bubbling completely.e The yeast was feeding on the sugar. When the
yeast cells respired, carbon dioxide was released.When they boiled the yeast they killed it, sorespiration stopped and the mixture stoppedbubbling.
