13/04/23Plant cells vs. Animal cellsPlant cells vs. Animal cellsBoth types of cell have these: Only plant cells
have these:
Nucleus
Cytoplasm
Cell wall
Large vacuole
Cell membrane
1)
2)
3)
6)
7)
Mitochondria – Energy is released here by respiration
4)
Chloroplasts
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Specialised cellsSpecialised cellsConsider the root hair cell in plants:
It was “suited” to its job of taking in water and nutrients in 2 ways:
1) It had a large surface area
2) It had a thin cell membrane
The sperm cell is an example of a specialised ANIMAL cell:
Strong tail for swimming
Vacuole containing enzymes
13/04/23More specialised animal More specialised animal cellscells
Red Blood Cell
Carries oxygen around the body
No nucleus, large surface area, packed with haemoglobin
I.D:
Function:
Features:
White blood cell
Egg cell (ovum)
Ciliated epithelial cell
Nerve cell (neurone)
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Specialised cellsSpecialised cellsArtery and vein
Eye
Compact bone
Blood
Areolar tissue (lung)
Lung
Stratified epithelium (skin)
Columnar epithelium (intestine)
Duodenum (small intestine)
Kidney
Spinal chord
Liver
Ileum (small intestine)
Stomach
Ciliated epithelial (windpipe)
Adipose tissue (fat)
Myelinated nerve
Skin & sebaceous (“oil-producing”) gland
Testis
Striated (normal) muscle
Non-striated muscle (e.g. stomach)
Cardiac (heart) muscle
Cerebellum (brain)
Ovary
Pancreas
13/04/23Cells, tissues, organs and Cells, tissues, organs and systemssystems
Basically, all living things are made up of cells…
A group of CELLS makes up a TISSUE
A group of TISSUES makes up an ORGAN
A group of ORGANS makes up a SYSTEM
A group of SYSTEMS make up an ORGANISM
13/04/23Some systems in the human Some systems in the human bodybody
Muscular system Skeletal system
Circulatory system
Respiratory system
Digestive system
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DiffusionDiffusionDiffusion is when something travels from an area of high concentration to an area of low concentration. For example, consider the scent from a hamburger…
The “scent particles” from this hamburger are in high
concentration here:
Eventually they will “diffuse” out into this
area of low concentration:
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DiffusionDiffusion
Cells use diffusion to swap the oxygen they need for the carbon dioxide they no longer want:
Other examples of where diffusion happens in humans:
Alveoli in the lungs Villi in the intestines
Oxygen diffuses in
Out goes waste CO2
13/04/23The digestive systemThe digestive systemThe whole point of digestion is to break down our food so that we can get the bits we need from it…
The main foods affected are CARBOHYDRATES – these are broken down into GLUCOSE
PROTEINS – these are broken down into amino acids
FATS (LIPIDS) – These are broken down into fatty acids and glycerol
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The small intestineThe small intestineThis is where the “small parts” are absorbed into our blood stream…
Glucose gets absorbed into
the blood
Everything else passes
into the large intestine
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EnzymesEnzymesEnzymes are chemicals produced by the body to help _______. When they react with food they break it down into ______ pieces which can then pass into the ______:
Carbohydrase (produced in the mouth, pancreas and small intestine) breaks _______ (a carbohydrate) down into glucose:
Protease (produced in the stomach, pancreas and small intestine) breaks _______ down into amino acids:
Lipase (produced in the pancreas and small intestine) breaks fats (_____) down into fatty acids and glycerol:
Words – blood, lipids, proteins, digestion, starch, smaller
Blo
od
stre
am
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The Model IntestineThe Model IntestineMethod:
1) Put some water into two boiling tubes and test the water for starch and glucose
2) Place the starch into the visking tube bag, add some enzyme and wash the outside
3) Place some starch WITHOUT enzyme in another visking tube bag
4) Place both visking tubes into the separate boiling tubes and start the stopclock
5) Test the water around the visking tubes for starch and glucose every two minutes
6) After ten minutes test the water one last time and then test the solutions in the visking tube bag
1) Why did the starch stay inside the visking tube?
2) What difference did adding the enzyme make? What did it do to the starch?
3) Where did the glucose go?
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Bile and the liverBile and the liverBile is a chemical produced in
the liver and stored in the gall bladder. It has 2 functions:
1) It neutralises stomach acid and produces alkaline conditions for enzymes to work in
2) It emulsifies (“breaks down” fats:
Fat globules
Fat droplets
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BreathingBreathing
13/04/23The Respiratory SystemThe Respiratory System
Ribs – to protect the
chest
Bronchioles
Bronchi Trachea – has stiff rings of cartilage to prevent it collapsing
Rib muscles – to raise and lower the ribs
Lung
Diaphragm – muscular sheet
Alveoli (“air sacs”) – gas
exchange takes place here
13/04/23Gas exchangeGas exchange
Alveoli are very good at exchanging gases because…
1) They have a LARGE surface area
2) They have a good blood supply
3) They are moist
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BreathingBreathing
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(Aerobic) Respiration(Aerobic) Respiration
Words – breathing, energy, Mrs Gren, respiration, food
A while ago we learnt about ___ ______. Each of these life processes needs ENERGY. ___________ is the process our bodies use to produce this energy:
Glucose + oxygen water + carbon dioxide + ENERGY
The glucose we need comes from ______ and the oxygen from _________. Water and carbon dioxide are breathed out. The MAIN product of this equation is _________.
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Anaerobic respirationAnaerobic respirationUnlike aerobic respiration, anaerobic respiration is when energy is provided WITHOUT needing _________:
This happens when the body can’t provide oxygen quick enough for __________ respiration to take place.
Anaerobic respiration produces energy much _______ than aerobic respiration but only produces 1/20th as much.
Lactic acid is also produced, and this can build up in muscles causing ______ and an oxygen ______.
This “debt” then needs to be “repaid” by deep breathing to ________ the lactic acid.
Words – debt, oxygen, fatigue, oxidise, aerobic, quicker
Glucose lactic acid + a bit of energy
13/04/23Aerobic vs. anaerobic Aerobic vs. anaerobic respirationrespiration
Similarities
Differences
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The Circulatory systemThe Circulatory systemThe circulatory system is responsible for pumping ______ around the body. We need blood to be taken around the body because blood contains ________ and _______. These are needed so that all the ____ in our bodies can produce _____ through _________.
The main organs in the circulatory system are the _____, the lungs and the kidneys.
Words – energy, heart, blood, glucose, respiration, oxygen, cells
13/04/23The “Double Circulatory” The “Double Circulatory” SystemSystem
1. Deoxygenated blood is pumped from the heart to the lungs
3. The oxygenated blood is then pumped to the rest of the body
2. The blood receives oxygen and is pumped back to the heart
4. The oxygen leaves the blood to be used for respiration in the body and the blood goes back to the heart
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The HeartThe Heart1. Deoxygenated blood (i.e. blood without oxygen) enters through the vena cava into the right atrium
2. It’s then pumped through the tricuspid valve into the right ventricle
3. It’s then pumped through the semi-lunar valve up to the lungs through the pulmonary artery
4. Oxygenated blood from the lungs enters through the pulmonary vein into the left atrium
5. It’s then pumped through the bicuspid valve into the left ventricle
6. It’s then pumped out of the aorta to the rest of the body
13/04/23Arteries, veins and Arteries, veins and capillariescapillaries
Arteries carry high pressure blood away from the heart.
They have smaller lumen and no valves.
Veins carry low pressure blood back to the heart. They have thinner, less elastic walls
and have valves to prevent backflow of blood.
Capillaries have thin walls (one cell thick) to
allow glucose and oxygen to pass through.
Also used to connect arteries to veins.
“Lumen”
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The four parts of bloodThe four parts of blood1. RED BLOOD CELLS – contain haemoglobin and carry ______ around the body. They have no _______ and a large surface area.2. PLATELETS – small bits of cells that lie around waiting for a cut to happen so that they can ____ (for a scab).
3. WHITE BLOOD CELLS – kill invading _______ by producing _________ or engulfing (“eating”) the microbe.
These three are all carried around by the PLASMA (a straw-coloured liquid). Plasma transports CO2 and ______ as well as taking away waste products to the ______.
Words – antibodies, clot, kidneys, oxygen, nucleus, glucose, microbes.
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MicrobesMicrobesMicrobes are micro organisms that can cause diseases. They can enter the body in a number of ways:
…or other natural openings…
They can be breathed in through the mouth or nose
They can enter through cuts or bites in the skin
13/04/23DiseaseDiseaseA disease is any condition where the body isn’t working as it should. This could be caused by a malfunction in the body (as with diabetes), or it could be caused by the two types of MICROBE:
Step 1: The white blood cell “sees” the antigen (microbe)
Step 2: The cell produces antibodies to “fit” the antigen
Step 3: The antibodies fit onto the antigens and cause them to “clump”
Step 4: The antigens are “eaten” by the white blood cells
You’re going down
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Fighting diseaseFighting diseaseNATURAL IMMUNITY
This is when antibodies are produced by a person when needed or they are passed on by the mother during pregnancy.
ARTIFICIAL IMMUNITY
Can be done in two ways:
1) A vaccine with dead microbes is injected – the body is “tricked” into producing antibodies ready for the real thing. This is called PASSIVE IMMUNISATION
2) The antibodies are injected directly into the body – this is called ACTIVE IMMUNISATION.
