Edexcel International GCSE Biology Hard PPQ Q1. The diagrams show the female and male reproductive systems. The table lists some events that take place in the female reproductive system, some that take place in the male reproductive system, and some that take place in both. Complete the table by giving the letter, or letters, to indicate where each event takes place. The first one has been done for you. fertilisation P release of oestrogen Q meiosis Q and V repair of uterus lining R implantation of embryo R formation of gametes Q and V
Q2. Describe the stages by which a bacterium can be genetically modified to produce large amounts of a named human protein. (5) Human DNA/ gene/ allele Restriction enzyme Ligase Same restriction enzyme Plasmid Vector Recombinant (DNA/ plasmid) Insulin/ factor VIII/ names protein Q3. Describe the stages in the production of cloned mammals such as Dolly the sheep. Nucleus from body cell/ nucleus from adult cell (5) Nucleus from adult Egg/ ovum Remove nucleus from egg/ enucleate (from egg) Nucleus into empty egg cell Electricity Mitosis Embryo Uterus/ womb Surrogate mother
Q4. The diagram shows some of the blood vessels and a nephron in the human kidney. The numbers represent the concentration of glucose at various places in the blood vessels and in the nephron, in arbitrary units. (a) Explain how the structure of the blood vessels entering and leaving the glomerulus help to move glucose into the Bowman s capsule. Vessels entering in wider/ increased pressure Ultrafiltration (b) What type of blood vessels are found in the glomerulus? Capillaries (c) (i) Describe how glucose is reabsorbed from the nephron back into the blood. Active transport Low conc. to high conc. Energy (ii) Suggest why glucose needs to be returned to the blood. Respiration Energy Osmotic effect
Q5. The diagram shows a mammal heart with glass tubes, X and Y, securely attached to the vena cava and the pulmonary artery. Water was poured into tube X and rose up tube Y until both tubes were filled to the level shown. (a) The ventricles were squeezed once by hand. (i) Suggest what would happen to the level of water in tube X and in tube Y when the ventricles were squeezed. Same and Y up (ii) Explain why no water came out of the aorta when the ventricles were squeezed. Right and left side separate/ septum/ aorta/ connected to left side/ no answer in LHS Q6. The student concluded that both samples of food contained carbohydrates. Do you agree with this conclusion? Give reasons for your answer. Yes Both A and B Starch present
Q7. (a) What is meant by the term mutation? Rare/ random Change/ damage DNA/ gene/ allele/ gene (b) Smoking can increase the risk of developing coronary heart disease. Explain how coronary heart disease can cause death. Blocked/ narrowed/ clogged (5) Coronary artery Clot Fat/ cholesterol Less blood to heart Less oxygen/ less oxygenated Muscle (cells) Less respiration/ anaerobic respiration Lactic acid/ angina Heart attack/ heart stops/ cardiac arrest Q8. Describe how the tea grower could use a quadrat to estimate the total mass of tea plants growing in a large area of land. Weigh/ use a balance (3) Repeat/ several quadrates Calculate average Random/ scale/ multiply
Q9. Scientists obtain blood samples from an athlete s vein. To do this they use a sterile needle attached to a syringe. Suggest one reason why the scientists could not obtain a blood sample from a capillary. Wider lumen Too small Q10. Cystic fibrosis is an inherited condition. It is caused by a recessive allele (d). The non-cystic fibrosis allele is dominant (D). The diagram shows how cystic fibrosis was inherited in a family. DD The only person in the family member who has cystic fibrosis Dd dd DD Dd dd How many people in this family do not have cystic fibrosis? 11
Q11. The passage describes cell division and reproduction in humans. Complete the passage by writing a suitable word or words in each of the spaces. (8) Fully grown adults can produce sex cells or... gametes called sperm and eggs. The... sperm cells are much smaller than the... egg cells and have a powerful... tail to enable them to swim. The cell division used to make sex cells is called... meiosis and in males this takes place in the... testis. The sperm cells pass out of the male along a tube called the... urethra and into the female s body, then through the cervix and into the... oviduct in which fertilisation takes place. Q12. (a) Antibiotics are chemicals used to kill pathogens that cause infections. (i) Name the type of organism that make antibiotics. fungi (ii) Name the type of pathogen that is killed by antibiotics. bacteria (b) Some antibiotics are no longer effective in killing pathogens. Use your knowledge of natural selection to explain why. Mutation (5) Variation Gene/ allele/ DNA Survive/ not killed Resistant Reproduce/ multiply/ replicate/ breed/ produce/ offspring Pass on gene/ DNA/ allele
Q13. The total mass of the organisms at each level in the pyramid decreases as you move up the pyramid. Explain why. Energy loss/ not all transferred (4) Respiration Excretion/ urine Egestion/ not digested/ faeces Not all of each organism eaten Some organism die/ decompose Movement Heat loss/ thermoregulation Q14. This apparatus can be used to investigate the rate of water uptake by a leafy shoot. (a) Describe one precaution you would take when setting up this apparatus. water/ air-tight/ dry leaves/ cut under water/ cut stem at an angle (b) Give two environmental conditions you could vary in the laboratory when investigating the rate of water uptake by a leafy shoot. 1. wind 2. light 3. humidity 4. temperature (4) Condition... How I could obtain a range of different values... 1. Fan at high and low speed 2. Lamp close and far 3. Clear plastic bag 4. Air conditioning/ room thermostat
Condition... How I could obtain a range of different values... Q15. To produce large amounts of human insulin the genetically modified bacteria are grown in a fermenter. Describe an investigation to find out if temperature affects the amount of insulin made by genetically modified bacteria. Your answer should include experimental details and be written in full sentences and paragraphs. C different temperatures (6) O same species/ same bacteria/ mass/ amount/ number of bacteria R repeat M measure insulin M concentration/ mass/ volume S same ph/ food/ oxygen/ time S type of fermenter/ sterile
Q16. (a) Describe how ventilation of the lungs occurs when a person breathes in. (4) Diaphragm Contract Flattens/ moves down/ lowers Intercostal muscles Ribs move up/ out/ ribcage expands Volume increases Pressure increases (b) Smoking cigarettes inside public buildings has been banned in many countries. (i) Suggest why governments have banned smoking cigarettes inside public buildings. Passive smoking/ others inhale smoke (3) Causes cancer/ contains carcinogen Asthma/ emphysema/ COPD/ bronchitis/ infection Carbon monoxide/ bind with haemoglobin Causes CVD/ heart disease Discourage smoking (ii) Suggest why children are particularly at risk from breathing in smoke from other people s cigarettes. Slows growth/ development/ still growing/ not fully developed Children smaller/ lungs are smaller Q17. Some people in the survey did not know anything about cloning. The process had to be described to them before they made a decision. Describe the process of cloning an adult animal using a named example. Dolly, Molly/ Polly/ Snuppy/ Copy cat/ Ralph/ Injaz/ Cupid/ Diana (6) Nucleus from body/ diploid cell put into empty/ enucleated egg cell Electricity/ shock Mitosis/ cell division Embryo
Uterus/ womb Surrogate Q18. The amount of light falling on plant leaves is an abiotic (non-living) factor that affects photosynthesis. (a) The leaves of plants that live in the shade (low light) are different to the leaves of plants that live in full sunlight. (i) Suggest why leaves from plants that live in the shade are darker green than leaves from plants that live in full sunlight. More chlorophyll/ more chloroplasts Absorb/ trap/ capture/ obtain/ light (ii) Explain why leaves from plants that live in the shade are thinner than leaves from plants that live in full sunlight. A Less distance/ cells near surface/ less of a barrier Light reaches/ trapped/ absorbed B Humid C Less photosynthesis Less/ no cuticle Less growth (b) The rate of photosynthesis changes during the day. (i) Explain the factors that affect the rate of photosynthesis in the early morning. Less photosynthesis (3) Less light/ less sun Lower temperature which affects enzymes Lower temperature which affects enzymes/ kinetic energy/ molecule movement/ collisions Fewer stomata open/ stomata less open/ closed
(ii) Explain the factors that affect the rate of photosynthesis in the early afternoon. More photosynthesis (3) More light/ sun Higher temperature affects enzymes/ kinetic energy/ molecular movement/ collisions Stomata open Low CO 2 slow photosynthesis Limit photosynthesis (c) Describe how you could compare the rate of photosynthesis in two different plant species. Measure oxygen/ starch/ change in CO 2 (4) Count bubbles/ volume gas syringe/ iodine/ hydro carbonate Same time Age/ mass/ surface area Light/ temperature/ CO 2 Q19. Explain why young plants absorb more mineral ions when air is bubbled through the solutions. Oxygen (3) Respiration Energy Active transport
Q20. The diagram shows a cell from the human nervous system. (a) (i) Name the structure labelled A. Nucleus (ii) Name the structure labelled B. Axon/ cytoplasm (iii) Draw an arrow on the diagram to show the direction of a nerve impulse. (b) Describe the role of this neurone in a simple reflex arc. Impulse Muscle/ gland/ effector Q21. Logs are decomposed by fungi. (a) Describe how fungi decompose tree logs. Hyphae/ mycelium (4) Enzymes Extracellular/ onto wood/ outside organism Digest/ digestive/ breakdown Carbon dioxide/ water Saprotroph/ saprophyte/ saprobiont
A garden bench is painted with a fungicide solution. This prevents the wood being decomposed because fungicide kills fungi. There are different fungicides that can be used. (b) Design an investigation to find out which fungicide is best at preventing the decomposition of wooden logs. Your answer should include experimental details and be written in full sentences. C different fungicides (6) O same logs/ same wood / same tree / same bench / same species / same age of wood R more than one log used/ several logs/ repeat M measure mass/ weight of wood before and after/ change in mass/ weight of wood M reference to state time period S 1 and S 2 same oxygen/ temperature/ moisture/ volume of fungicide/ amount/ exposed to same fungi/ same mass of fungi End of the test