GCSE Biology Practice Test 8 – 60 Questions with Answers (AQA 8461)

Q1. Why is an electron microscope used to study cells in detail?

• (A) It shows cells in colour more clearly
• (B) It can view living cells more easily
• (C) It has a much higher magnification and resolution than a light microscope
• (D) It uses light to magnify specimens

Q2. A cell image is 15 mm long and the real cell is 0.03 mm long. What is the magnification?

• (A) 50
• (B) 450
• (C) 500
• (D) 5000

Q3. Which structure do plant cells use to make food using light?

• (A) Nucleus
• (B) Mitochondrion
• (C) Ribosome
• (D) Chloroplast

Q4. How is a nerve cell adapted to its function?

• (A) It has a long axon that carries impulses over distances
• (B) It contains many chloroplasts
• (C) It has a large permanent vacuole
• (D) It can contract strongly

Q5. Why do muscle cells contain many mitochondria?

• (A) Because muscle cells carry out photosynthesis
• (B) Because muscle contraction needs a large supply of energy
• (C) Because muscle cells store genetic information
• (D) Because muscle cells produce antibodies

Q6. How is a sperm cell adapted for reaching an egg?

• (A) It has a tail for swimming and many mitochondria for energy
• (B) It has chloroplasts for photosynthesis
• (C) It has a thick cell wall for protection
• (D) It has a large vacuole for storage

Q7. After mitosis, how does the chromosome number in each new cell compare with the parent cell?

• (A) It is the same as in the parent cell
• (B) It is half the number in the parent cell
• (C) It is double the number in the parent cell
• (D) It is a quarter of the number in the parent cell

Q8. How does a larger surface area affect the rate of diffusion into a cell?

• (A) It increases the rate because more particles can cross at once
• (B) It decreases the rate because particles spread out
• (C) It has no effect on diffusion
• (D) It stops diffusion by blocking the membrane

Q9. Why do growers use tissue culture from meristems?

• (A) To create new species by sexual reproduction
• (B) To increase genetic variation in crops
• (C) To produce many identical, disease-free plants quickly
• (D) To make plants grow without water

Q10. Why does amylase from saliva stop working well in the stomach?

• (A) Bile neutralises the enzyme in the stomach
• (B) The stomach is too warm for enzymes
• (C) Stomach acid denatures the enzyme by changing its shape
• (D) Amylase only works on proteins

Q11. How does bile help lipase digest fats?

• (A) It breaks fats directly into glucose
• (B) It changes the pH to acidic for lipase
• (C) It breaks large fat droplets into smaller ones, increasing surface area for lipase
• (D) It carries fats into the blood

Q12. Which enzymes are produced by the pancreas?

• (A) Amylase, protease and lipase
• (B) Amylase only
• (C) Pepsin only
• (D) Insulin and glucagon only

Q13. Which vessel carries oxygenated blood at high pressure from the heart to the body?

• (A) The pulmonary artery
• (B) The vena cava
• (C) The aorta
• (D) The pulmonary vein

Q14. Which vessel returns deoxygenated blood from the body to the right atrium?

• (A) The aorta
• (B) The vena cava
• (C) The pulmonary vein
• (D) The coronary artery

Q15. What does blood plasma transport?

• (A) Oxygen bound to haemoglobin only
• (B) Red blood cells only
• (C) Nerve impulses to muscles
• (D) Dissolved nutrients, hormones, carbon dioxide, urea and other substances

Q16. Plasma makes up about 55 percent of blood. What does plasma transport?

• (A) Oxygen bound to haemoglobin only
• (B) Only white blood cells
• (C) Only hormones
• (D) Dissolved nutrients, hormones, carbon dioxide, urea and plasma proteins

Q17. Why does the heart muscle need its own blood supply through coronary arteries?

• (A) Because the heart stores blood for the body
• (B) Because coronary arteries carry blood to the lungs
• (C) Because heart muscle cells need oxygen and glucose for continuous contraction
• (D) Because the heart cannot use blood inside its chambers

Q18. Which leaf tissue carries out most photosynthesis?

• (A) Epidermis
• (B) Palisade mesophyll
• (C) Xylem
• (D) Guard cells

Q19. Salmonella food poisoning is caused by which type of pathogen, and how is it often spread?

• (A) A virus spread by mosquitoes
• (B) A fungus spread by spores in soil
• (C) A protist spread in drinking water
• (D) Bacteria spread in contaminated food

Q20. Rose black spot is a plant disease that does what?

• (A) A virus causes roots to swell and rot
• (B) A fungus causes dark spots on leaves, which may fall and reduce photosynthesis
• (C) Bacteria block the xylem completely
• (D) A protist eats the flower petals

Q21. How does HIV affect the body?

• (A) It destroys red blood cells and causes anaemia only
• (B) It blocks digestion in the small intestine
• (C) It prevents blood clotting
• (D) It attacks white blood cells of the immune system, reducing the ability to fight infection

Q22. Which is a first line of defence against pathogens entering the body?

• (A) Antibody production in the blood
• (B) Phagocytosis by white blood cells
• (C) The skin acting as a barrier
• (D) Vaccination with a weakened pathogen

Q23. Why is a second infection by the same pathogen usually fought more quickly?

• (A) The skin becomes thicker after the first infection
• (B) Memory cells recognise the pathogen and produce antibodies rapidly
• (C) Antibiotics remain in the blood permanently
• (D) White blood cells become larger

Q24. Painkillers are useful in treating illness, but what do they not do?

• (A) They do not relieve pain
• (B) They do not reduce a fever
• (C) They do not work for headaches
• (D) They do not kill the pathogen causing the illness

Q25. What is tested during the preclinical stage of drug development?

• (A) Whether the drug sells well in shops
• (B) The drug in large groups of patients only
• (C) The colour and taste of the drug
• (D) Whether the drug is toxic and effective, using cells, tissues and animals

Q26. How does the waxy cuticle help protect a plant from disease?

• (A) It produces antibodies against fungi
• (B) It forms a physical barrier that makes entry difficult for pathogens
• (C) It attracts insects that eat pathogens
• (D) It closes the stomata permanently

Q27. How does an antiseptic differ from an antibiotic?

• (A) An antiseptic only kills viruses
• (B) An antibiotic only works on skin
• (C) There is no difference between them
• (D) An antiseptic kills pathogens outside the body, for example on skin, while an antibiotic works inside the body

Q28. In a pondweed experiment, why does counting bubbles give a measure of photosynthesis rate?

• (A) The bubbles are carbon dioxide taken in by the plant
• (B) The bubbles are nitrogen from the water
• (C) The bubbles are oxygen released by photosynthesis
• (D) The bubbles show the rate of respiration only

Q29. What happens to the rate of photosynthesis if temperature rises well above the optimum?

• (A) The rate keeps rising without limit
• (B) The rate stays exactly the same
• (C) The rate falls because enzymes involved are denatured
• (D) Photosynthesis stops because light is blocked

Q30. How does a large leaf surface area help photosynthesis?

• (A) It captures more light energy
• (B) It reduces water loss to zero
• (C) It increases the thickness of the leaf
• (D) It prevents carbon dioxide entering

Q31. Glucose from photosynthesis can be converted into cellulose. What is cellulose used for in plants?

• (A) To store energy in seeds
• (B) To make proteins
• (C) To make strong cell walls
• (D) To attract pollinators

Q32. Energy released by respiration is used for which process in animals?

• (A) Photosynthesis in the skin
• (B) Absorbing light in the eye only
• (C) Muscle contraction and maintaining body temperature
• (D) Producing oxygen in the lungs

Q33. In the production of alcoholic drinks, what does yeast fermentation produce?

• (A) Lactic acid, which flavours the drink
• (B) Ethanol, which is the alcohol in the drink
• (C) Glucose, which sweetens the drink
• (D) Oxygen, which carbonates the drink

Q34. Why do muscles feel tired after prolonged vigorous exercise?

• (A) Glucose builds up in muscle cells
• (B) Oxygen builds up in the blood
• (C) Lactic acid builds up from anaerobic respiration
• (D) Muscles run out of water completely

Q35. Why might a very active person need more energy in their diet than a less active person?

• (A) Because active people digest food more slowly
• (B) Because exercise reduces the need for respiration
• (C) Because active people store more fat automatically
• (D) Because a higher metabolic rate and more muscle activity use more energy

Q36. At night, what gas do plants release overall, and why?

• (A) Carbon dioxide, because they respire but do not photosynthesise in the dark
• (B) Oxygen, because they photosynthesise at night
• (C) Nitrogen, because they fix nitrogen at night
• (D) No gas, because plants stop respiring at night

Q37. What is the role of a coordination centre?

• (A) It receives information from receptors and coordinates a response
• (B) It detects changes in the environment
• (C) It carries out the final response
• (D) It produces hormones in the blood

Q38. Why is a reflex action faster than a conscious action?

• (A) Reflexes use hormones instead of nerves
• (B) Reflexes skip the receptor
• (C) Reflexes use thicker bones
• (D) The impulse does not have to travel to the conscious part of the brain

Q39. How does myelin around an axon affect a nerve impulse?

• (A) It slows down transmission
• (B) It stops the impulse completely
• (C) It changes the impulse into a hormone
• (D) It speeds up transmission of the impulse

Q40. Thyroxine is produced by which gland, and what does it control?

• (A) The thyroid gland; it controls metabolic rate
• (B) The adrenal gland; it controls blood glucose
• (C) The pituitary gland; it controls growth only
• (D) The pancreas; it controls insulin release

Q41. In the menstrual cycle, what does follicle stimulating hormone (FSH) do?

• (A) It triggers ovulation directly
• (B) It maintains the uterus lining
• (C) It breaks down the uterus lining
• (D) It stimulates an egg to mature in a follicle in the ovary

Q42. What does oestrogen do in the menstrual cycle?

• (A) It causes menstruation by breaking down the lining
• (B) It stimulates repair and thickening of the uterus lining
• (C) It prevents eggs maturing
• (D) It lowers body temperature

Q43. Why is glucose normally absent from urine?

• (A) Because it is completely reabsorbed from kidney tubules back into the blood
• (B) Because glucose is destroyed in the bladder
• (C) Because the kidney does not filter glucose
• (D) Because glucose is stored in the kidney

Q44. How does vasoconstriction help in cold conditions?

• (A) Wider skin blood vessels increase heat loss
• (B) Sweat production increases
• (C) Hairs lie flat to lose heat
• (D) Narrower skin blood vessels reduce heat loss from the blood

Q45. What is an advantage of sexual reproduction over asexual reproduction?

• (A) It always produces more offspring
• (B) It produces variation, which may help a species survive environmental change
• (C) It produces genetically identical offspring
• (D) It needs only one parent

Q46. In peas, tall (T) is dominant to dwarf (t). Two heterozygous tall plants (Tt) are crossed. What percentage of offspring are expected to be tall?

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

Q47. Two heterozygous parents (Aa x Aa) have children. What proportion is expected to be homozygous recessive (aa)?

• (A) All of them
• (B) One quarter
• (C) One half
• (D) None of them

Q48. Blood group is an example of which type of variation?

• (A) Continuous variation
• (B) Discontinuous variation
• (C) Environmental variation only
• (D) Variation caused by mutation only

Q49. How can antibiotic resistance evolve in bacteria?

• (A) Antibiotics directly change bacterial genes in every bacterium
• (B) Resistant bacteria survive antibiotic treatment and reproduce, passing on resistance
• (C) Bacteria learn to avoid antibiotics
• (D) Resistant bacteria are created by the antibiotic itself

Q50. What is a disadvantage of selective breeding?

• (A) It can reduce genetic variation and increase inherited health problems through inbreeding
• (B) It always makes organisms weaker in one generation
• (C) It prevents any variation arising
• (D) It makes offspring genetically identical to wild organisms

Q51. Golden rice is genetically modified to contain which vitamin?

• (A) Vitamin C
• (B) Vitamin D
• (C) Vitamin B12
• (D) Vitamin A

Q52. What is meant by a species in classification?

• (A) A group of organisms that can interbreed to produce fertile offspring
• (B) Any group of organisms that look similar
• (C) All organisms living in one habitat
• (D) Organisms with the same genus name only

Q53. In a food web, a hawk eats both rabbits and mice. If mice decline, what may happen to rabbit numbers?

• (A) Rabbits increase because hawks stop hunting
• (B) Hawks eat more rabbits, so rabbit numbers may fall
• (C) Hawks become producers
• (D) Rabbits are unaffected because food webs are fixed

Q54. In a pyramid of biomass, what is usually true?

• (A) Top predators have the largest biomass
• (B) All levels have equal biomass
• (C) Producers have the largest biomass and each higher level has less
• (D) Decomposers have the largest biomass

Q55. Plants in the same habitat compete for which resources?

• (A) Prey animals and mates
• (B) Light, water, mineral ions and space
• (C) Nesting sites and mates only
• (D) Oxygen and carbon dioxide only

Q56. Which of these is an abiotic factor affecting plant distribution?

• (A) Soil pH
• (B) Competition with other plants
• (C) Predation by herbivores
• (D) Disease spread by fungi

Q57. Which of these is a biotic factor?

• (A) Predation
• (B) Temperature
• (C) Rainfall
• (D) Soil mineral content

Q58. Burning fossil fuels affects the carbon cycle by doing what?

• (A) Releasing carbon dioxide that was locked up for millions of years
• (B) Removing carbon dioxide from the air permanently
• (C) Converting carbon dioxide into oxygen
• (D) Stopping photosynthesis in plants

Q59. Which is a likely consequence of global warming?

• (A) A fall in average global temperatures
• (B) Less rainfall everywhere on Earth
• (C) A decrease in carbon dioxide in the air
• (D) Sea levels rising as ice melts and water expands

Q60. How does draining a wetland for building damage an ecosystem?

• (A) It increases the number of aquatic species
• (B) It improves water quality in all nearby rivers
• (C) It destroys habitats and reduces biodiversity
• (D) It creates new habitats for wetland birds