1 Sample Paper 1 Section A 1. Any 4 (5 marks each) (a) defence against disease, production of antibodies (b) fallopian tube (c) endotherm (d) throat/pharynx (e) liver 2. 6 (3 marks each) + (2 marks) (a) a biological catalyst (made of protein) (b) amylase/catalase/protease (c) substrate (d) conversion of starch to sugar/tanning of leather/making cheese/alcohol etc. (e) A (f) temperature/enzyme concentration/substrate concentration 3. Any 4 (5 marks each) (a) insects (b) soil (c) sun (d) thermometer (e) energy 4. 6 (3 marks each) + (2 marks) (a) 3 marks for each label (b) put X on exit of optic nerve (c) blind spot (d) any 2: ear, skin, nose, tongue 5. 6 (3 marks each) + (2 marks) (a) white bread (b) cabbage (c) white bread
Transcript
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Sample Paper 1
Section A
1. Any 4 (5 marks each)
(a) defence against disease, production of antibodies
(b) fallopian tube
(c) endotherm
(d) throat/pharynx
(e) liver
2. 6 (3 marks each) + (2 marks)
(a) a biological catalyst (made of protein)
(b) amylase/catalase/protease
(c) substrate
(d) conversion of starch to sugar/tanning of leather/making cheese/alcohol etc.
(e) any 2: as a solvent/as a medium for reactions/transport/maintain internal environment
6. 6 (3 marks each) + (2 marks)
(a) Y, reason: cell loses water (to dilute the salt)
(b) X
(c) osmosis
(d) A – cell wall, B – vacuole, C – cytoplasm
Section B
7. (a) (i) the pacemaker (3 marks)
(ii) location: in wall (at top) of right atrium (3 marks)
(b) (i) any 2 (3 marks each): scalpel/dissecting tray/forceps/pins/seeker/scissors/disposable gloves/flag labels
(ii) presence of coronary blood vessels across face of heart from its left to right/feel thickness of ventricle walls, thicker should be on your right(3 marks)
(iii) (3 marks)
(iv) thin/membrane/tough (3 marks)
(v) left ventricle wall is thicker (3 marks) it has to pump blood all around the body (3 marks)
(vi) flag label is positioned in structure you wish to identify (3 marks)
8. (a) any 1 (3 marks): fructose/maltose/galactose/lactosefunction: for energy/as respiratory substrate (3 marks)
(b) (i) Benedict’s solution or Fehlings 1 and 11 (3 marks)
(ii) labels: thermometer (2 marks), beaker/water bath (2 marks), Benedict’s solution or Fehlings (2 marks)
(iii) 4 (3 marks each)
(iv) tube A acts as a control (3 marks)
9.
Exercise 1
(a) (i) chloroplasts (3 marks)
Tube Colour before test Colour after test
A Blue Blue
B Blue Brick-red
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(ii) leaf/green stem (3 marks)
(b) (i) diagram (0–3–6 marks) (must show light source and thermometer for 6), labels any 3 (1 mark each): thermometer/light source/plant/water
(ii) by adding different amounts of sodium hydrogen carbonate (sodium bicarbonate) (3 marks)
(iii) factor (3 marks) + how kept constant (3 marks)light intensity – keep lamp at fixed distancetemperature – use water bath at fixed temperature
(iv) count the bubbles of gas released/in a given time 2 points (3 marks each)
Exercise 2
(a) (i) chloroplasts (3 marks)
(ii) leaf/green stem (3 marks)
(b) (i) diagram (0–3–6 marks) (must show light source and thermometer for 6), labels any 3 (1 mark each): thermometer/light source/plant/water
(ii) by moving a lamp of same wattage different distances or by having lamp at same distance but change wattage of bulb (3 marks)
(iii) factor (3 marks) + how kept constant (3 marks)carbon dioxide – by adding excess sodium hydrogen carbonate (sodium bicarbonate)temperature – use water bath at fixed temperature
(iv) count the bubbles of gas released/in a given time 2 points (3 marks each).
Section C
10. (a) Name (3 marks), description or map, 2 points (3 marks)
(b) (i) 3 animals (3 marks each)2 identification features for one animal: e.g. size legs/wings/colour/shape/coat or hair (3 marks each)
(ii) 1 adaptation (3 marks)
(iii) labelled diagram of any 1 piece of equipment ( 0–3–6 marks), use(3 marks)
(c) (i) 7 (3 marks)
(ii) any 2 (3 marks each): mussel/limpet/ barnacle
(iii) small algae (3 marks)
(iv) small algae
→
limpet
→
dog whelk
→
crabsmall algae
→
barnacle
→
dog whelk
→
crab (3 marks)
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(v) mussels – little change (3 marks) because sea gulls and dog whelks would still eat them. (3 marks)
(ii) copy (3 marks) bases 1–T, 2–A, 3–G (3 marks each)
(iii) nucleus/chromosome (3 marks)
(iv) double helix (3 marks)
(v) double v single strand, T instead of U (3 marks each)
(c) (i) any 2: for growth/repair/metabolism (6 marks each)
(ii) 4 points (3 marks each): DNA codes for protein/DNA message transcribed to mRNA/mRNA travels to ribosome/message translated/amino acids form into chain/protein molecule folds
12. (a) a ductless gland/a gland that produces (secretes) hormones (6 marks)1 example: thyroid/pituitary (3 marks)
(b) neuron diagram (0–3 marks); any 5 labels (3 marks each) axon/dendrite/cell body/nucleus/myelinnsheath/schwann cell/synaptic knobs; any 1 function for any 3 parts labelled (3 marks each)
(c) (i) for one disease: cause (6 marks), prevention (6 marks) and treatment (6 marks)
(ii) any one pair of statements (3 marks for each statement = 6 marks): motor neurons carry message from CNS, sensory neurons carry messages to the CNS/Motor neurons have cell body at one end of the cell, sensory neurons have cell body somewhere along the length of the axon
13. (a) 2(3 marks each): fusion of female nucleus with male nucleus/to form zygoteFertilisation takes place in the ovary/ovule/embryo sac (3 marks)
(b) (i) A – petal, B – carpel/style, C – anther/stamen, D – sepal (3 marks each)
(ii) any 2 (3 marks each): flower large/flowers parts inside flower/has petals/has nectaries
(iii) any 2 (3 marks each): flower parts outside/ no nectary/small size/no large petals
(c) (i) the ovary becomes the fruit (3 marks)
(ii) 2 reasons (3 marks each): avoid competition/prevent overcrowding/allows new areas to be colonised
(iii) 2 methods (3 marks each): water/animal wind/self; 2 points on adaptation (6 marks each): bouyant/hooks or tasty/light or have tufts or wings/ dry out and burst open or have holes to release seeds
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14. Answer any two of (a), (b), (c).
(a) 3 points (3 marks) aerobic: produces more energy/uses oxygen/products differ/occurs in two stages/occurs in cytoplasm and mitochondria
(i) carbon dioxide (3 marks)
(ii) to keep out oxygen/to maintain anaerobic conditions (3 marks)
(iii) alcohol (3 marks)
(iv) any 1 of the following/3 points (3 marks each)distil solution/in a condenser/alcohol boils at 78ºC
or
add potassium dichromate/warm gently/green colour indicates presence of alcohol
or
add potassium iodide solution and sodium hyperchlorite solution/warm gently/yellow crystals indicate presence of alcohol
(v) use dead yeast instead of live yeast (3 marks)
(b) (i) 2 (3 marks): a sex cell, haploid
(ii) gametes (X) (X) x (X) (Y) 4 (2 marks each)offspring (XX) (XX) (XY) (XY) 4 (2 marks each)sex of offspring girl girl boy boy 4 (2 marks each)
7. (a) (i) it is the basic unit of life/all living things are made of them (3 marks)
(ii) cell membranes, cytoplasm, mitochondria (accept nucleus) (1 mark each)
(b) (i) A – eye piece, B – stage, C – fine focus wheel, D – diaphragm/iris(3 marks each)
(ii) to control the amount of light getting to specimen/to adjust contrast(3 marks)
(iii) to prevent air bubbles (3 marks)
(iv) 2 points (3 marks each): place stain at one side/tissue paper at the other or place the specimen in a drop of stain/re-apply the coverslip
8. (a) (i) name, e.g, sea shore (3 marks)
(ii) 3 abiotic factors (1 mark each): e.g. salinity/light intensity/temperature/aspect
(b) (i) to measure any one factor: name of factor (3 marks), method 4 points(3 marks each)
(ii)
(iii) to prevent them from being eaten by predators (3 marks)
9. (a) (i) dormancy (3 marks)
(ii) one advantage: allows seed to ripen/colonise new habitat/survive unfavourable conditions (3 marks)
(b) (i) that moisture is needed (3 marks)
(ii) the seeds would not have germinated (3 marks)
(iii) to compare the germination with and without water/to make it a fair test (3 marks)
(iv) a single seed might be damaged or diseased (3 marks)
(v) place in an incubator/closed cupboard/cardboard box (3 marks)
(vi) C would go blue-black (3 marks)it is a food store (3 marks)
Section C
10. (a) 3 definitions (3 marks each)
(b) name of ecosystem (3 marks)
(i) name of organism (3 marks)
30 30×9
--------------------- 9009
----------- (3 marks) 100 3 marks( )==
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(ii) habitat (3 marks)
(iii) method of nutrition (3 marks)
(iv) for animal – food (3 marks)
(v) for plant identification feature (3 marks)
(vi) one biotic factor (3 marks), how it is affected (3 marks)
(vii) one adaptation (3 marks)
(c) (i) cause (6 marks), effect (6 marks)
(ii) any one conservation practice (6 marks), explained (6 marks)
11. (a) 3 definitions (3 marks each)
(c) (i) Dexoyrobonucleic acid (DNA) (6 marks)
(ii) helped our understanding of genetics (6 marks)
(iii) in 2003 (6 marks)
(iv) all the genes that make up a human being (6 marks)
12. (a) definition (3 marks): organisms so small that they can (normally) only be seen using a microscope/ microscopic organisms, 3 types (2 marks each): Viruses, Bacteria, Fungi
(b) (i) Diagram (0–3 marks), 3 labels (2 marks each)
(ii) a circular piece of DNA (3 marks)
(iii) A – sweat duct, B – hair, C-sebaceous gland (3 marks each)
(iv) Skin acts as a barrier/secretes chemicals that kill bacteria/sweat(3 marks)White blood cells engulf bacteria/produce antibodies (3 marks)
(c) (i) to prevent spread of disease/infection (3 marks)
(ii) sterile means free of all micro-organisms (3 marks), any 1 method (3 marks): pressure cook/ autoclave
(iii) any 2 (3 marks each): wash hands before and after working with micro-organisms or swab benches with disinfectant/flame inoculating loops/minimal opening of plates safe disposal of materials/use of sterile equipment and media/maintain aseptic conditions
(iv) pathogen (6 marks), any 1 bacterial disease (3 marks): e.g. TB, step throat/diptheria/salmonella food poisoning/cholera/syphilis etc.
(b) gametesgenotypes of progenyphenotypes of progeny
(PR )(PR Pr)
Pink
(Pr)(PR PR)
Red
x (PR)(PR Pr)
Pink
(Pr)(Pr Pr)White
4 (3 marks each)3 (3 marks each)3 (2 marks each)
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13. (a) (i) definition (6 marks)
(ii) any 1: sweat/urine/carbon dioxide (3 marks)
(b) (i) A – renal artery, B – kidney, C – ureter, D – bladder, E – urethra (2 marks each)
(ii) store urine (3 marks)
(iii) diagram (0–3–5 marks), 3 labels (2 marks each)
(c) (i) the cortex (3 marks)
(ii) 2 points (3 marks each): Reabsorption is the taking back/of useful substances/into the blood/It is necessary to make sure the good substances are not lost from the body (with the urine) (6 marks)
(a) (i) graph (3 marks), 2 axes labelled (3 marks each), 2 axes correctly spaced, (3 marks each)
(ii) as light intensity increases the rate increases/up to light intensity 4 when it levels out, 2 points (3 marks each)
(iii) 2.6 (3 marks)
(iv) oxygen (3 marks)
(v) the rate would be slower (3 marks)
(b) (i) correct order – B, D, F, A, E, C, all 5 correct (12 marks), 4 correct(9 marks) 2 correct (6 marks)
(ii) messenger RNA/a chemical that reads the DNA code/carries DNA code to ribosome (6 marks)
(iii) ribosomes (3 marks)
(iv) amylase/catalase/protease (3 marks)
(v) hormone (3 marks), example (3 marks)
(c) (i) name, function, location (3 marks each)
(ii) name, function, location (3 marks each)
(iii) 1. micropropagation/cloning/tissue culture (3 marks)/2. mitosis(3 marks)/3. any 2 (3 marks) e.g. in agriculture/to grow crops quickly/with specific features such as disease resistance; in horticulture to grow house plants with specific features
15. Answer any two of (a), (b), (c).
(a) (i) diagram (0–3–5 marks), 5 labels (2 marks each)
(ii) X on fallopian tube, Y on ovary, Z at cervix (3 marks each)
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(iii) one method (3 marks), example (3 marks)
(b) (i) A – semicircular canal, B – cochlea, C – hammer (ossicle, bone), D – eardrum (3 marks each)
(ii) A – balance, B – hearing, C – transfer vibrations (to inner ear) (3 marks each)
(iii) it balances air pressure/either side of the eardrum, 2 points (3 marks each)
(c) notes for any 3 (3 + 3 + 2 + 2 marks): state what it is/where it is made formed/what it looks like/what it does/where it works/one or more examples/as appropriate to the term
(i) tropisms: growth tendancy of plants/to a stimulus/e.g. phototropism/to light/geotropism/to force of gravity/benefit to the plant
(ii) dormancy: period of rest or low metabolism/prevents new seedlings being killed off/by unfavourable conditions/e.g. frost/lack of water etc./plant still viable/allows embryo to mature
(iii) plant growth regulators: chemicals produced by plants to control growth and development/produced in growing tips/any two named examples such as auxin or ethene/and two matching functions e.g. cell elongation/ripening of fruit
(iv) modified plant storage organs: plant stems/roots/leaves/modified to store food/e.g. potato tuber – stem/onion bulb – leaves/carrot – tap root/to help plant survive the winter/underground
(v) pollination: transfer of pollen/from anther to stigma/necessary for fertilisation/two types/self and cross/both explained/agents of pollination e.g. insects/wind/adaptation of plant for different type
(a) F (b) T (c) T (d) F (e) T (f) F (g) T (h) T (i) T (j) F
5. 5 (2 + 2 marks each)
(a) cell wall – plant cells only/made of cellulose; membrane – present in all cells/made of lipoprotein
(b) haploid – having a single set of chromosomes/diploid – having a double set
(c) aerobic produces more energy/needs oxygen/anaerobic produces less energy/not in presence of oxygen
(d) DNA – found in nucleus/makes up the genes/codes for protein/AGTC; double strand RNA – found in ribosomes/translates protein code/has U instead of T/single strand
(e) osmosis is diffusion of water across a semi-permeable membrane; diffusion is movement of molecules from high to low concentration
6. 6 (3 marks) + (2 marks)
(a) H
2
O, O
2
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(b) it absorbs the light energy
(c) chloroplast
(d) air/respiration
(e) (i) provides food (ii) provides oxygen
Section B
7. (a) (i) a biological catalyst (3 marks)
(ii) protein (3 marks)
(b) (i) 3 points (3 marks each): add enzyme to sodium alginate solution/and mix well/draw solution into syringe/add to calcium chloride/drop by drop
(ii) points of description and/or labelled account, 3 points (3 marks each): put beads in burette (tap funnel)/pour in test solution e.g. starch/collect run off/test run off for product/on a time basis
test for product: Benedict’s/reducing sugar test/potassium dichromate (alcohol) (3 marks)
(iii) the enzyme does not get used up/can be used over and over/cheaper (3 marks)
8. (a) (i) they make their own food/photosynthesize (3 marks)
(ii) 1 advantage (3 marks): easily dispersed/avoid competition with mother plant
(iv) average number = 96/10 (3 marks) = 9.6 (3 marks)
9. (a) (i) DNA and protein (3 marks)
(ii) 46 (3 marks)
(b) (i) 2 marks for each correctly placed
(ii) onion/kiwi etc. (3 marks)
(iii) appearance: fine threads (3 marks), colour: white (3 marks)
(iv) to break open the cells/to protect the DNA (3 marks)
C E A H G B D F
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Section C
10. (a) 3 definitions (3 marks each)
(b) (i) 1. Clare (nn), 2. her mother (Nn) (3 marks each)
(c) (i) Species, 2 points (3 marks each): group of organisms that have characteristics in common/and can successfully interbreed, Mutation, 2 points (3 marks each): a change in a gene/or chromosome.
(ii) any 2 (3 marks each): radiation/chemicals/spontaneous (natural)/carcinogens, e.g. in cigarette smoke
(iii) 2 points (3 marks each): Mutations cause changes in genes/or chromosomes/if they happen in a gamete producing cell then the mutation can be inherited/and show up in the next generation
11. (a) not being able to conceive a baby (6 marks), one cause in the female (3 marks)
(b) (i) fallopian tube (3 marks)
(ii) meiosis (3 marks)
(iii) sperm (3 marks)
(iv) diagram (0–3 marks), any 3 labels (1 mark each)
(v) puberty (10 –12 years) (3 marks)
(vi) testosterone (3 marks), any other function (3 marks)
(vii) low sperm count/ low testosterone production (3 marks)
(c) (i) A – amniotic fluid, B – umbilical cord, C – cervix (1 mark each)
(ii) to protect the foetus (3 mark)
(iii) 2 points (3 marks each): from the mother’s tissue and/the foetus
(iv) any 2 (3 marks each): oxygen, urea, carbon dioxide, digested food, minerals
(v) any 1 (3 marks): drugs, alcohol, nicotine
(vi) diffusion (3 marks)
12. (a) any 3 (3 marks each): support/ protection/ production of blood cells/movement
(b) (i) diagram (0–3–6 marks), 3 labels (2 marks each)
(ii) Cavity: stores marrow, Spongy bone: reduce weight and Compact bone: for strength (3 marks each)
(iii) 1. Tendons, 2. Ligaments (3 marks each)
(ii) genotype of parentsgametesgenotypes of offspringphenotypes of offspring
(Nn)(N) (n)(Nn)
normal,
xx
(NN)(N)
(NN)normal
2(3 marks each)3(2 marks each)2(3 marks each)
(3 marks)
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(c) (i) disc of cartilage (3 marks), prevents bones rubbing off each other/prevents friction (3 marks)
(ii) C (3 marks), 5 lumbar vertebrae (3 marks)
(iii) any 1 (3 marks): hip bones/rib cage/collar bones
(iv) one cause (6 marks) and prevention (3 marks)
13. (a) Name e.g. muscle (6 marks), description shape of cells/feature etc (3 marks)
(b) (i) A – cytoplasm, B – cell membrane, C – nucleus. (3 marks each)
(ii) mitochondria/ribosomes (3 marks each)
(iii) rinse mouth/remove using sterile/swab or spatula 2 (3 marks), transfer to drop of water/ on a slide/ cover with cover slip 2 (3 marks)
(c) (i) definition (3 marks)
(ii) 4 diagrams 4 (3 marks) labels chromosome, fibres, nuclear membrane, poles any 3 (1 marks), sequence correct (3 marks)
(iii) any 1 cause: smoking/radiation/viruses (3 marks)
14. Answer any two of (a), (b), (c).
(a) (i) 9 (1 mark each)
(ii) oak leaves (3 marks)
(iii) they would be well protected, camouflaged (3 marks)
(iv) diagram (0–3 marks),any 1 label (3 marks)/place pooter tube/over insect/suck through other tube/to trap insect/3 points (3 marks each)
(b) (i) definition (6 marks)
(ii) pollutant (3 marks), any 2 effects (3 marks each): oil/sulfur dioxide/chemical effluent/methane/e.g. sulfur dioxide can cause acid rain/reduce crop yields/destroy forests/damage buildings/cause bronchitis etc.; plastic bottles/bags/tins/waste food/paint/batteries etc./e.g. waste food can be unsightly/smell/cause disease etc.
(iii) any 1 control measure (6 marks): recycle material/reduce production/treat harmful material before disposal/controlled incineration etc.
(iii) any 2 proteins (3 marks each) e.g. amylase/thyroxine/haemoglobin; any 2 matching functions (3 marks each) e.g. amylase breaks down starch/thyroxine controls metabolism/haemoglobin is a pigment
(vi) the bacteria become resistant, then the antibiotic can no longer cure the illness (3 marks)
(b) (i) definition (6 marks): production of new plants without the fusion of gametes
(ii) any 2 (3 marks): modified root – tubers/leaves – bulbs/stems – runners/tubers
(iii) for any method in (ii) name of plant (3 marks), method described,3 points (3 marks each)
(iv) one advantage (3 marks): quicker/maintains genotype/reliable; one disadvantage (3 marks): new plants grow close together increasing competition/they are all susceptible to the same diseases
(c) (i) X – pulmonary artery, Y – right ventricle, Z – aorta(3 marks each)
(ii) pulmonary vein, left atrium, left ventricle, aorta, hepatic artery, hepatic vein, vena cava, any 5 (2 marks each)
(iii) bone marrow (3 marks)
(iv) they carry oxygen (3 marks)
(v) O, A, B, AB (0–3–5 marks for all)
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Sample Paper 4
Section A
1. Any 4 (5 marks each)
(a) genotype
(b) to make protein
(c) photosynthesis
(d) 46
(e) protease/pepsin/erepsin
2. Any 4 (5 marks each)
3. 5 (4 marks each)
(a) tadpole
(b) water weeds
(c) lake
(d) water weeds
(e) water weeds
→
tadpoles
→
small fish
→
large fish
4. Any 6 (3 marks) + (2 marks)
(a) A – dermal, B – ground, C – vascular
(b) stoma
(c) to control opening and closing of stoma/gas exchange
(ii) one breath in and out = a single breath, count the number of breaths you take in a minute or the number of times your chest raises in a minute(3 marks)
(iii) get breathing rate at rest/repeat x 2/get average/take exercise/find breathing rate again/repeat x 2/get average/vary the exercise/repeat/compare results, 4 points (3 marks)
(iv) to give a more accurate result (3 marks)
(v) you might not register every breath, your time-keeping might not be accurate (3 marks)
Exercise 2
(a) (i) the contraction and expansion of the arteries as blood is pumped through (3 marks)
(ii) place fingers (not thumb) of one hand against inside of lower arm opposite, or against temple, or neck (3 marks)
(b) (i) get pulse rate at rest/repeat x 2/get average/take exercise/find pulse rate again/repeat x 2/get average/vary the exercise/repeat/compare results [If using datalogging equipment: name make of instrument/set up data harvester/attach sensor to earlobe (belt)/take readings/repeat x 2/get
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average/take exercise/repeat collection of data/repeat procedure/get averages]/5 points (3 marks)
(ii) 72 beats per minute (3 marks)
(iii) you might not count all the pulses/you or your partner might not time the count accurately (3 marks)
(iv) pulse rate increases with increased exercise (3 marks)
8. (a) (i) any function, e.g. digestion of large molecules (food)/synthesis of new materials/respiration etc. (3 marks)
(ii) any three enzymes (1 mark each)
(b) (i) graph plot (6 marks), axes labelled (3 marks), axes to fit (3 marks)
(ii) pH 8 (3 marks)
(iii) use water bath at temperature to suit enzyme (3 marks)use same volume of enzyme or same percentage solution (3 marks)
(iv) use universal indicator paper or solution (3 marks)
9. (a) (i) growth response of plant shoot to light (3 marks)
(ii) meristem (3 marks)
(b) (i) diagram (0–3 marks), any 3 labels (1 mark each)
(ii) method, 4 points (3 marks each)
(iii) results (3 marks each)
(iv) conclusion (3 marks)
Section C
10. (a) 3 definitions (3 marks each)
(b) (i) 4, 2, 6, 1, 5, 3 (6 marks)
(ii) an educated guess/an idea/a possible explanation (6 marks)
(iii) as a reference/to be the first to show something/to share the knowledge (3 marks)
(iv) Sample size is important to avoid bias/to ensure a fair or valid test/the more sample you have the more accurate will be the results (6 marks). Using replicates is important to show that the outcome wasn’t just a ‘once off’ event/ to verify the results (6 marks)
(c) (i) to compare the number of bacteria in fresh and 3-day old milk/to show there are fewer bacteria in fresh milk (6 marks)
(ii) the control acts as a comparison/provides a reference point/ make it a fair test (6 marks)
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(iii) C (3 marks)
(iv) keep everything as sterile as possible/ seal plates/ safe disposal of material (3 marks)
(v) the 3 day old milk has more bacteria/ the fresher the milk the fewer the bacteria (6 marks)
11. (a) (i) definition (3 marks)
(ii) in chromosomes/nucleus (3 marks)
(iii) allele (3 marks)
(ii) protection/hold moisture (prevent water loss) (6 marks)
(c) (i) 3 explanations (3 + 3 each)
(ii) production of growth hormone/ blood clotting factors etc. (3 marks), producing rice with the gene for vitamin A/ flava-sava tomatoes (3 marks), production of insulin using bacteria (3 marks)
12. (a) (i) secondary circulatory system (3 marks)
(ii) any 2 functions (3 marks each)
(b) (i) Diagram (0–3–6 marks), 6 labels (2 marks each)
(ii) blood flow (6 marks)
(c) (i) CO2 – lungs, Glucose – small intestine, liver/any body organ, Oxygen – any organ, e.g. stomach etc., Insulin – pancreas 5 (3 marks)
(ii) increase blood pressure/prevent oxygen reaching heart muscle (6 marks)any 2 points (3 marks each): smoking can cause clots/thicken arteries/lower oxygen to heart/increase carbon monoxide, which prevents oxygen transport etc.
13. (a) ability to react to changes/(inside and outside an organism) (3 marks)any 2 ways (3 marks each): plants respond by growing in the direction of light, force of gravity and water
(b) (i) central nervous system and peripheral nervous system (3 marks each)
(ii) white blood cells engulf bacteria/produce antibodies against them (3 marks)
(iii) 1. copy diagram, 3 labels (2 marks each), 2. message picked up by heat receptor/goes along sensory neuron/to CNS/inter neuron/to motor neuron/out to effector, i.e. muscle/hand pulls away/message also goes to brain 4(3 marks)
(c) (i) X – pituitary gland, Y – thyroid (3 marks each)
10. (a) Leaf: photosynthesis/transpiration/gas exchange (3 marks)Stem: support aerial parts/conduct water/ minerals and food (3 marks)Flower: for reproduction (3 marks)
(b) (i) stamen: male part of flower/consists of anther and filament/produces pollen (3 marks)Vascular bundles: place where food and water are transported/have xylem and phloem cells (3 marks)
(ii) petals attract pollinators (3 marks)
(iii) absorption of water/minerals/stores food (3 marks)
(iv) monocot and reason (3 marks)
(v) diagram (0–3 marks), 3 labels (3 marks each)
(c) (i) any 2 (3 marks each): carbon dioxide, water, minerals
(ii) oxygen, carbohydrate 2(3 marks)Uses: oxygen for respiration, carbohydrate for respiration/to make other chemicals/to store as starch/to form cell structures, e.g. cellulose in cell walls 2(3 marks)
(iii) phloem (3 marks)
(iv) roots/stems (3 marks)
11. (a) (i) definition (6 marks)
(ii) to produce gametes (eggs and sperm) (3 marks)
(b) (i) to get enough light (for photosynthesis) (3 marks)
(ii) Cross 1.Genotypes of parents: (TT) x (tt)Gametes (T) x (t)Genotypes of offspring (Tt)Phenotype tall 4(2 marks)
Cross 2.Parents (Tt) x Tt)Gametes (T), (t) x (T), (t)Genotypes of offspring (TT), (Tt), (tt)Phenotypes (matching) Tall Tall Dwarf 16(1 mark)
(c) (i) any 2 (3 marks each): differences in the sugar/U replaces T in RNA/RNA found inside and outside nucleus, DNA found in nucleus
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(ii) Coding DNA is used to form proteins, non-coding DNA is junk DNA (6 marks)
(iii) DNA replication 4 points (3 marks each): Two DNA stands untwist/using enzymes/‘free’ nucleotides in the nucleus move into position/A=T and G=C/complementary chains (strands) form alongside the existing chains/to form two identical helices
12. (a) Ability to keep internal environment constant (6 marks)Necessary to allow all the reactions in the body to work properly (3 marks).
(b) (i) hair stands up (3 marks) muscle contracts (3 marks)Reason: to trap air for insulation (3 marks)
(ii) 1. because you sweat (3 marks), evaporation of sweat (3 marks) takesheat from the body (3 marks)
2. heat is carried by the blood (3 marks)/blood capillaries move tosurface/and dilate (3 marks)/ heat radiates out (3 marks)
(c) (i) A – hepatic artery, B – hepatic portal vein. 2(3 marks)
(ii) A (3 marks)
(iii) any 2 (3 marks each): detoxifies wastes/makes bile/stores vitamins/converts glucose to glycogen etc.
(iv) insulin/glucagons (3 marks)
(v) Insulin lowers blood sugar level/by taking glucose into cellsGlucagon raises blood sugar level/by releasing glucose from cells(6 marks)
13. (a) The release of energy from food (6 marks)Needed to provide the energy to carry out all the activities of the body (3 marks)
(b) (i) definition (6 marks)
(ii) trapped in fibres/beads/of sodium alginate (3 marks), advantage: can be used over and over/cheap/don’t mix with product (6 marks)
(iii) 1. protease (3 marks)2. egg/ blood/ketchup (3 marks)3. enzymes are affected by high temperatures (3 marks)
Aerobic Anaerobic
(i) Need for oxygen yes (3 marks) no (3 marks)
(ii) Site in cell cytoplasm + mitochondria(3 + 3 marks)
cytoplasm (3 marks)
(iii) Products CO
2
, H
2
O, energy(3 marks)
alcohol + carbon dioxide+ energy (3 marks)
(iv) Energy a lot (3 marks) a little (3 marks)
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14. Answer any two of (a), (b), (c).
(a) (i) any two: double blind – to make sure neither the tester nor the tested know the procedure and outcome/it is a means of avoiding bias(6 marks), random samples – avoids bias (6 marks), replicates – ensure result is not a ‘once off’ event (6 marks), large samples – ensures individual differences do not influence the results (6 marks)
(ii) 1. the need for oxygen for seeds to germinate/need for the correct temperature (3 marks), 2. 3 results (2 marks each): A - germination, B and C – no germination; reasons: A because it has moisture, warmth and oxygen (3 marks), B has no warmth (3 marks), C has no oxygen(3 marks)
(b) (i) 90% (3 marks)
(ii) wind and birds (3 marks each)
(iii) keep it covered (3 marks)
(iv) when it gets into streams and nearby land (3 marks)
(v) methane (3 marks) formed from bacteria/breaking down organic waste,2 points (3 marks each)
(vi) recover the gas as an energy source (3 marks)
(vii) minimise (reduce) and recyle (3 marks)
(c) (i) 2 definitions (6 marks each)
(ii) 1. to make proteins (3 marks), 2. A – nitrogen fixation, B – decay/ decomposition (3 marks each), 3. nitrifying (3 marks), 4. they have root nodules that house nitrogen fixing bacteria (6 marks)
15. Answer any two of (a), (b), (c).
(a) (i) any 3 (3 marks each): plants/animals/fungi/protista (protoctista)/monera
(ii) name (3 marks): bacteria/amoeba/yeast; kingdom (3 marks): monera/protista/fungi
(iii) Rhizopus/yeast/any named fungus (6 marks)
(iv) they are non-cellular (6 marks)
(v) ‘flu’, cold, chicken pox, AIDS, etc. (3 marks)
(b) (i) any 2 (3 marks each): cerebrum/cerebellum/medulla oblongata/hypothalamus/pituitary gland; 2 functions (3 marks each)
(ii) 1. nerves carry messages into an out of the brain (6 marks), 2. sense organs have the sensory nerve endings/pick up the stimulus (6 marks)/3. muscles and glands carry out the action (6 marks)
(c) (i) graph plot (3 marks), axes labelled (3 marks), correct use of axes (3 marks)
(ii) loss of water vapour from the surface of plant (6 marks)
(iii) from graph time = 13.00 +/– 15 mins (6 marks)
(iv) from 8.30 to 11.00 (3 marks)
(v) presence of a cuticle/opening and closing of stomata/any one (6 marks)
