GCSE Biology Practice Test 9 – 60 Questions with Answers (AQA 8461)

Q1. How do ciliated epithelial cells in the airways help defend the body?

• (A) They produce antibodies against pathogens
• (B) They absorb oxygen into the blood
• (C) They divide to make new lung tissue
• (D) Their cilia sweep mucus containing trapped dust and pathogens upwards

Q2. How is an egg cell adapted to its function?

• (A) It has a tail for swimming
• (B) It contains many chloroplasts
• (C) It has a thick cell wall
• (D) It is large and contains nutrient stores in its cytoplasm for the early embryo

Q3. What happens during cell differentiation?

• (A) All cells keep exactly the same structure
• (B) Chromosome number doubles in every cell
• (C) Cells develop different structures to suit particular functions
• (D) Cells lose their nucleus permanently

Q4. A microscope image is 10 mm long at a magnification of 200. What is the real size of the specimen?

• (A) 0.05 mm
• (B) 0.5 mm
• (C) 2000 mm
• (D) 0.005 mm

Q5. Why does oxygen diffuse from alveoli into the blood?

• (A) Oxygen concentration is lower in the alveoli than in the blood
• (B) Oxygen concentration is higher in the alveoli than in the blood
• (C) Carbon dioxide pushes oxygen into the blood
• (D) The alveoli actively pump oxygen using energy

Q6. What happens to an animal cell placed in a concentrated salt solution?

• (A) Water enters the cell and it bursts
• (B) The cell becomes turgid
• (C) Water leaves the cell by osmosis and the cell shrinks
• (D) Nothing happens because animal cells have a wall

Q7. How are amino acids absorbed from the small intestine when their concentration in the gut is lower than in blood cells?

• (A) By osmosis through the villi
• (B) By active transport using energy
• (C) By diffusion down a gradient
• (D) By photosynthesis in gut cells

Q8. What must happen to DNA before a cell divides by mitosis?

• (A) The DNA is halved and not copied
• (B) The DNA is destroyed
• (C) The DNA is copied so each new cell receives a full set
• (D) The DNA moves into the mitochondria

Q9. Why is each enzyme specific to one substrate?

• (A) All enzymes have the same active site
• (B) Its active site has a shape complementary to that substrate
• (C) Enzymes change shape to fit any substrate
• (D) Substrates change shape to fit the enzyme

Q10. What happens to enzyme activity as temperature rises above the optimum?

• (A) Activity falls because the enzyme is denatured
• (B) Activity keeps rising indefinitely
• (C) Activity stays at the optimum level
• (D) Activity falls because the substrate is used up

Q11. How does mucus protect the stomach?

• (A) It forms a layer that prevents acid damaging the stomach wall
• (B) It digests proteins in the stomach
• (C) It neutralises all stomach acid
• (D) It absorbs amino acids

Q12. Where do fatty acids and glycerol pass after absorption in the small intestine?

• (A) Into lacteals, the small lymph vessels in villi
• (B) Directly into the aorta
• (C) Into the stomach for further digestion
• (D) Into the large intestine

Q13. What sets the basic rhythm of the heartbeat?

• (A) A group of cells in the right atrium acting as a pacemaker
• (B) The brain sending an impulse for every beat
• (C) Valves opening and closing
• (D) The lungs expanding and contracting

Q14. Which blood component is mainly responsible for defending against pathogens?

• (A) White blood cells
• (B) Red blood cells
• (C) Platelets
• (D) Plasma proteins only

Q15. How does wind increase the rate of transpiration?

• (A) It closes the stomata
• (B) It reduces light reaching the leaf
• (C) It cools the leaf so less water evaporates
• (D) It blows away water vapour around leaves, maintaining a steep diffusion gradient

Q16. What do leaf veins contain?

• (A) Only chloroplasts
• (B) Only guard cells
• (C) Xylem and phloem for transport
• (D) Only mesophyll cells

Q17. What is an advantage of a double circulation?

• (A) Blood is re-pressurised in the heart before being pumped to the body, maintaining a fast flow
• (B) Blood passes through the heart only once
• (C) Oxygenated and deoxygenated blood mix in the heart
• (D) The heart does not need valves

Q18. Cholera is spread mainly by which route?

• (A) Mosquito bites
• (B) Droplets from coughing
• (C) Drinking water contaminated with faeces containing the bacteria
• (D) Contact with infected skin

Q19. Tuberculosis is caused by bacteria that mainly affect which organ and spread how?

• (A) The skin, spread by direct contact
• (B) The lungs, spread in droplets from coughs and sneezes
• (C) The liver, spread in food
• (D) The intestines, spread by mosquitoes

Q20. Ringworm is an example of which type of infection?

• (A) A bacterial infection of the lungs
• (B) A fungal infection of the skin
• (C) A viral infection of the blood
• (D) A protist infection of the gut

Q21. How can bed nets help reduce malaria?

• (A) They kill the protist in the blood
• (B) They prevent mosquitoes biting people and transmitting the protist
• (C) They cure infected people
• (D) They drain standing water

Q22. How do antibodies help destroy a pathogen after binding to it?

• (A) They burst red blood cells
• (B) They change the pathogen into a vaccine
• (C) They mark it so phagocytes can recognise and engulf it more easily
• (D) They block all blood flow to the area

Q23. What does the MMR vaccine protect against?

• (A) Malaria, measles and ringworm
• (B) Meningitis, malaria and rubella
• (C) Measles, mumps and rubella
• (D) Measles only

Q24. How does a new antibiotic-resistant strain of bacteria arise?

• (A) The antibiotic creates resistance in all bacteria at once
• (B) Bacteria choose to become resistant
• (C) A mutation creates a resistant variant, which survives treatment and multiplies
• (D) Resistance is passed from humans to bacteria

Q25. In clinical trials on patients, what is mainly being tested?

• (A) Whether the drug can be made cheaply
• (B) Whether the drug is effective and what dose works safely
• (C) Whether healthy people enjoy taking it
• (D) Whether animals tolerate the drug

Q26. Gonorrhoea is spread by which route and caused by which type of pathogen?

• (A) Mosquito bites; virus
• (B) Sexual contact; bacteria
• (C) Contaminated water; protist
• (D) Airborne droplets; fungus

Q27. What energy change occurs in photosynthesis?

• (A) Chemical energy is converted into light energy
• (B) Light energy is converted into chemical energy stored in glucose
• (C) Heat energy is converted into sound energy
• (D) Electrical energy is converted into kinetic energy

Q28. In an experiment, a light is moved further from pondweed and bubbling slows. Why?

• (A) Carbon dioxide concentration rises with distance
• (B) Light intensity falls with distance, so photosynthesis slows
• (C) The water becomes warmer with distance
• (D) The plant uses less oxygen at greater distances

Q29. At low light intensity, why does increasing carbon dioxide have little effect on photosynthesis rate?

• (A) Because light, not carbon dioxide, is the limiting factor
• (B) Because carbon dioxide is toxic at low light
• (C) Because chlorophyll is destroyed by carbon dioxide
• (D) Because plants cannot absorb carbon dioxide in dim light

Q30. Which word equation summarises anaerobic respiration in muscle?

• (A) Glucose + oxygen -> carbon dioxide + water + energy
• (B) Glucose -> ethanol + carbon dioxide + energy
• (C) Glucose -> lactic acid + energy
• (D) Carbon dioxide + water -> glucose + oxygen

Q31. Plants use glucose to make amino acids. What else is needed for this?

• (A) Oxygen from respiration only
• (B) Carbon dioxide from the air only
• (C) Nitrate ions absorbed from the soil
• (D) Water from the roots only

Q32. Why do many seeds store energy as fats and oils?

• (A) Fats release more energy per gram than carbohydrates when respired
• (B) Fats are easier to dissolve in water
• (C) Fats prevent seeds germinating
• (D) Fats attract animals to eat seeds

Q33. Why does breathing rate stay high for a while after vigorous exercise stops?

• (A) To remove glucose from the blood
• (B) To cool the lungs down
• (C) To take in extra oxygen to break down lactic acid and repay the oxygen debt
• (D) To increase carbon dioxide in the blood

Q34. What happens to excess amino acids in the liver?

• (A) They are converted directly into glucose only
• (B) They are stored as protein in the liver
• (C) They are excreted unchanged in urine
• (D) They are deaminated, forming urea for excretion

Q35. Why is starch a good storage carbohydrate in plants?

• (A) It dissolves easily and spreads through the plant
• (B) It is sweet and attracts animals
• (C) It can be used directly in respiration without conversion
• (D) It is insoluble, so it does not affect water movement by osmosis

Q36. What does a sensory neurone do?

• (A) It carries impulses from the central nervous system to an effector
• (B) It connects two motor neurones in a muscle
• (C) It produces hormones in response to a stimulus
• (D) It carries impulses from a receptor towards the central nervous system

Q37. In bright light, what happens to the pupil and why?

• (A) It dilates to let in more light
• (B) It stays the same size
• (C) It closes completely
• (D) It constricts to reduce the light reaching the retina

Q38. Testosterone is produced where, and what does it do at puberty?

• (A) In the testes; it stimulates development of male secondary sexual characteristics
• (B) In the ovaries; it stimulates egg release
• (C) In the thyroid; it controls metabolic rate
• (D) In the adrenal glands; it controls blood glucose

Q39. In a typical 28-day menstrual cycle, when does ovulation usually occur?

• (A) On day 1
• (B) Around day 14
• (C) On day 28
• (D) On day 7

Q40. How does a combined oral contraceptive prevent pregnancy?

• (A) It kills sperm in the uterus
• (B) It blocks the fallopian tubes permanently
• (C) It destroys the uterus lining
• (D) It inhibits FSH so eggs do not mature and ovulation does not occur

Q41. What happens during in vitro fertilisation (IVF)?

• (A) Eggs are fertilised outside the body and an embryo is placed in the uterus
• (B) Eggs are fertilised inside the fallopian tube by surgery only
• (C) Sperm are injected into the uterus lining
• (D) The uterus lining is removed and replaced

Q42. Which sequence correctly shows the path of urine out of the body?

• (A) Bladder -> ureter -> kidney -> urethra
• (B) Kidney -> urethra -> bladder -> ureter
• (C) Kidney -> ureter -> bladder -> urethra
• (D) Ureter -> kidney -> urethra -> bladder

Q43. How does hair standing on end help in cold weather?

• (A) It traps a layer of insulating air next to the skin
• (B) It increases sweating
• (C) It widens blood vessels in the skin
• (D) It makes muscles contract

Q44. What effect do gibberellins have on seeds?

• (A) They prevent seeds germinating
• (B) They cause fruit to ripen
• (C) They promote germination by breaking dormancy
• (D) They cause shoots to bend away from light

Q45. How does the sequence of bases in a gene determine a protein?

• (A) It determines the size of the cell
• (B) It determines how many chromosomes a cell has
• (C) It determines the order of amino acids in the protein
• (D) It determines the number of ribosomes

Q46. Two carriers of a recessive condition (Aa) have children. What percentage are expected to be carriers (Aa)?

• (A) 25%
• (B) 75%
• (C) 100%
• (D) 50%

Q47. Huntington disease is caused by a dominant allele (H). If an affected heterozygous parent (Hh) has children with an unaffected parent (hh), what percentage are expected to be affected?

• (A) 25%
• (B) 75%
• (C) 100%
• (D) 50%

Q48. Where do new alleles come from?

• (A) Selective breeding only
• (B) Mutations that change the DNA base sequence
• (C) Changes in the environment during an organism lifetime
• (D) The mixing of chromosomes in mitosis

Q49. How can pesticide resistance develop in insects?

• (A) Pesticides change the genes of all insects equally
• (B) Insects develop thicker skins during their lifetime and pass this on
• (C) Resistant insects survive spraying and reproduce, passing resistance to offspring
• (D) Pesticides make insects stronger directly

Q50. Selective breeding of dairy cows has produced animals that do what?

• (A) Produce milk without eating
• (B) Give birth to identical twins always
• (C) Resist all diseases completely
• (D) Produce a much higher milk yield than wild ancestors

Q51. How does a genetically modified insect-resistant crop protect itself?

• (A) It contains a bacterial gene so it produces a protein toxic to insect pests
• (B) It is sprayed with more pesticide
• (C) It grows thorns to deter insects
• (D) It produces antibodies against insects

Q52. Which classification rank contains the largest number of different organisms?

• (A) Genus
• (B) Kingdom
• (C) Species
• (D) Family

Q53. A herbivore eats plant material, but only part of it becomes herbivore biomass. Why is much energy lost?

• (A) Some material is egested as faeces and much energy is used in respiration and movement
• (B) Herbivores cannot digest any plant material
• (C) All plant energy is stored as starch
• (D) Herbivores pass energy directly to decomposers only

Q54. If producers contain about 5000 kJ of energy, about how much is typically transferred to primary consumers?

• (A) About 5000 kJ
• (B) About 50 kJ
• (C) About 25000 kJ
• (D) About 500 kJ

Q55. What is the role of earthworms in decomposition?

• (A) They photosynthesise to make food for soil
• (B) They eat only living plant roots
• (C) They absorb carbon dioxide from soil
• (D) They are detritivores that break dead material into smaller pieces for microorganisms

Q56. How is carbon transferred from a producer to a consumer?

• (A) By feeding, when the consumer eats the producer
• (B) By photosynthesis in the consumer
• (C) By combustion in the consumer
• (D) By decay of the consumer

Q57. In the water cycle, what is condensation?

• (A) Water evaporating from the sea
• (B) Water vapour cooling to form liquid droplets in clouds
• (C) Rain falling to the ground
• (D) Water soaking into soil

Q58. How does the greenhouse effect warm the Earth?

• (A) Greenhouse gases block all sunlight reaching Earth
• (B) Greenhouse gases create heat by burning
• (C) Greenhouse gases reflect heat into space
• (D) Greenhouse gases absorb heat radiated from Earth and re-radiate it, trapping warmth

Q59. Flooded rice fields contribute to global warming by releasing which gas?

• (A) Oxygen
• (B) Nitrogen
• (C) Sulfur dioxide
• (D) Methane

Q60. How can an introduced non-native species reduce biodiversity?

• (A) It always increases the number of native species
• (B) It may outcompete native species for food and habitat
• (C) It prevents all predation
• (D) It improves soil for native plants