GCSE Biology Practice Test 18 – 60 Questions with Answers (AQA 8461)

Q1. Osmosis is the movement of water molecules across a partially permeable membrane from a dilute solution to a more concentrated solution. Which factor increases the rate of osmosis?

• (A) A steeper concentration gradient
• (B) A lower temperature
• (C) A smaller surface area
• (D) A thicker membrane

Q2. A root hair cell takes up mineral ions from soil water even when the ions are more concentrated inside the cell. Which process is this?

• (A) Diffusion
• (B) Active transport
• (C) Osmosis
• (D) Photosynthesis

Q3. As a cell grows larger, what happens to its surface area to volume ratio?

• (A) It increases
• (B) It stays the same
• (C) It decreases
• (D) It doubles each time

Q4. Which cell is adapted for carrying oxygen because it has no nucleus and a biconcave shape?

• (A) A white blood cell
• (B) A nerve cell
• (C) A palisade cell
• (D) A red blood cell

Q5. Which adaptation helps a sperm cell swim towards an egg?

• (A) A long tail and many mitochondria
• (B) A large vacuole
• (C) Many chloroplasts
• (D) A thick cell wall

Q6. Why do muscle cells contain large numbers of mitochondria?

• (A) Because muscles photosynthesise
• (B) Because muscle contraction needs a lot of energy
• (C) Because muscles store DNA
• (D) Because muscles make hormones

Q7. A palisade mesophyll cell is adapted for photosynthesis mainly because it contains many of which structure?

• (A) Ribosomes
• (B) Nuclei
• (C) Chloroplasts
• (D) Vacuoles

Q8. Ciliated epithelial cells line the airways. How do their cilia help protect the lungs?

• (A) They absorb oxygen into the blood
• (B) They produce antibodies
• (C) They contract to open the airways
• (D) They sweep mucus and trapped dust upwards away from the lungs

Q9. In a double circulatory system, blood passes through the heart how many times in one complete circuit?

• (A) Twice
• (B) Once
• (C) Four times
• (D) Three times

Q10. Which part of the blood is responsible for transporting oxygen around the body?

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

Q11. Platelets are important because they help with which process?

• (A) Carrying oxygen
• (B) Fighting infection
• (C) Blood clotting
• (D) Transporting hormones

Q12. White blood cells defend the body. Which of these is a way they do this?

• (A) Carrying carbon dioxide
• (B) Producing bile
• (C) Storing glucose
• (D) Engulfing and digesting pathogens

Q13. Plasma transports dissolved substances around the body. Which substance is NOT mainly carried in plasma?

• (A) Oxygen bound to haemoglobin
• (B) Carbon dioxide
• (C) Urea
• (D) Hormones

Q14. Coronary heart disease can be caused by fatty deposits building up in which vessels?

• (A) The pulmonary veins
• (B) The coronary arteries
• (C) The vena cava
• (D) Capillaries in the skin

Q15. A stent is used to treat coronary heart disease. What does it do?

• (A) It replaces a heart valve
• (B) It removes the heart
• (C) It holds a blocked artery open
• (D) It lowers cholesterol in the liver

Q16. Statins are drugs that can reduce the risk of heart disease by doing what?

• (A) Increasing heart rate
• (B) Thickening artery walls
• (C) Raising blood pressure
• (D) Lowering blood cholesterol levels

Q17. MRSA is difficult to treat because it is resistant to many antibiotics. What type of organism is MRSA?

• (A) A bacterium
• (B) A virus
• (C) A fungus
• (D) A protist

Q18. Drug development begins with testing a new drug on cells and tissues in the laboratory. What is this stage called?

• (A) Clinical trial
• (B) Preclinical testing
• (C) Double blind trial
• (D) Placebo testing

Q19. In a clinical trial, a placebo is given to some patients. What is a placebo?

• (A) A double dose of the drug
• (B) A vaccine
• (C) A dummy treatment with no active drug
• (D) An antibiotic

Q20. A double blind trial is one in which neither the patients nor the doctors know who receives the real drug. Why is this done?

• (A) To save money
• (B) To speed up recovery
• (C) To increase the dose
• (D) To remove bias from the results

Q21. Painkillers relieve symptoms but do not cure the cause of disease. Which statement best describes them?

• (A) They reduce pain without killing the pathogen
• (B) They kill bacteria
• (C) They stimulate antibody production
• (D) They replace vaccines

Q22. Which disease is spread by direct contact and by droplets in the air?

• (A) Malaria
• (B) Measles
• (C) Athlete’s foot only
• (D) Cholera only

Q23. Gonorrhoea is a sexually transmitted infection caused by which type of pathogen?

• (A) A virus
• (B) A fungus
• (C) A bacterium
• (D) A protist

Q24. HIV is a virus that attacks which cells of the immune system?

• (A) Red blood cells
• (B) Platelets
• (C) Nerve cells
• (D) White blood cells

Q25. Which substance do plants make from glucose and nitrate ions absorbed from the soil?

• (A) Amino acids for making proteins
• (B) Fatty acids only
• (C) Chlorophyll only
• (D) Starch only

Q26. A plant grown without nitrate ions shows poor growth and yellow leaves. What is the most likely explanation?

• (A) It cannot photosynthesise at all
• (B) It cannot make enough proteins and chlorophyll
• (C) It cannot absorb water
• (D) It cannot make starch

Q27. Limiting factors for photosynthesis can be investigated by changing one factor at a time. If carbon dioxide is increased but the rate stays the same, what can be concluded?

• (A) Light is always limiting
• (B) Temperature has no effect
• (C) Carbon dioxide was not the limiting factor under those conditions
• (D) Photosynthesis has stopped permanently

Q28. A student places pondweed in water with a lamp at different distances. What is the independent variable?

• (A) Number of bubbles per minute
• (B) Temperature of the water
• (C) Size of the pondweed piece
• (D) Distance of the lamp from the pondweed

Q29. In the pondweed experiment, why should the temperature be kept constant?

• (A) Because temperature also affects photosynthesis rate and could confuse the results
• (B) Because pondweed dies in warm water
• (C) Because bubbles stop at high temperature only
• (D) Because light intensity depends on temperature

Q30. Which gas is given off by pondweed during photosynthesis and forms bubbles?

• (A) Carbon dioxide
• (B) Oxygen
• (C) Nitrogen
• (D) Hydrogen

Q31. Respiration happens in which cells?

• (A) Only muscle cells
• (B) Only plant cells at night
• (C) All living cells
• (D) Only animal cells

Q32. Plants respire and photosynthesise. When is the rate of photosynthesis greater than the rate of respiration in a healthy plant in daylight?

• (A) At night
• (B) In darkness
• (C) When the plant is wilted
• (D) In bright daylight, when light is plentiful

Q33. At the compensation point, the rates of photosynthesis and respiration are equal. What is the net gas exchange?

• (A) No net uptake or release of carbon dioxide
• (B) Maximum oxygen release
• (C) Maximum carbon dioxide uptake
• (D) No oxygen is used

Q34. Oestrogen is produced by the ovaries. What is one of its roles?

• (A) It causes menstruation directly
• (B) It causes the uterus lining to build up
• (C) It produces sperm
• (D) It lowers body temperature

Q35. Progesterone maintains the uterus lining. If fertilisation does not occur, what happens to progesterone levels?

• (A) They rise sharply
• (B) They stay constant forever
• (C) They fall, and the lining breaks down
• (D) They convert to oestrogen

Q36. Fertility can be treated with FSH and LH. Why do these hormones help?

• (A) They block ovulation
• (B) They replace the uterus lining
• (C) They kill bacteria
• (D) They stimulate egg maturation and ovulation

Q37. In vitro fertilisation (IVF) involves fertilising eggs outside the body. Where are fertilised embryos then placed?

• (A) Into the uterus
• (B) Into the ovary
• (C) Into the bloodstream
• (D) Into the fallopian tube only by surgery always

Q38. Plant shoots grow towards light. What is this response called?

• (A) Negative phototropism
• (B) Positive phototropism
• (C) Positive gravitropism
• (D) Thigmotropism

Q39. Plant roots grow downwards in response to gravity. What is this called?

• (A) Negative phototropism
• (B) Positive phototropism
• (C) Positive gravitropism
• (D) Chemotropism

Q40. Auxin is a plant hormone. How does it cause a shoot to bend towards light?

• (A) It stops growth on the shaded side
• (B) It makes the light side grow faster
• (C) It closes stomata on the light side
• (D) It moves to the shaded side and causes faster cell elongation there

Q41. In roots, auxin has the opposite effect to shoots. What does high auxin concentration do in roots?

• (A) It inhibits cell elongation
• (B) It speeds up elongation greatly
• (C) It has no effect
• (D) It causes roots to grow upwards

Q42. Gibberellins are plant hormones used in agriculture. What is one use?

• (A) To ripen fruit only
• (B) To promote seed germination and stem elongation
• (C) To close stomata
• (D) To prevent flowering

Q43. Which characteristic shows continuous variation?

• (A) Blood group
• (B) Ability to roll the tongue as a simple yes or no
• (C) Height in humans
• (D) Number of fingers

Q44. Discontinuous variation is controlled by a small number of genes and shows distinct categories. Which is an example?

• (A) Height
• (B) Weight
• (C) Leaf length
• (D) Blood group

Q45. Evolution by natural selection requires variation, competition and survival of the fittest. Which statement best describes natural selection?

• (A) Organisms best adapted to their environment survive and pass on their genes
• (B) Organisms choose to change their genes
• (C) All organisms survive equally
• (D) Acquired characteristics are inherited

Q46. A population of moths lives on dark tree trunks after pollution darkens them. Which moths are most likely to survive?

• (A) Light moths, because they are brighter
• (B) Dark moths, because they are camouflaged from predators
• (C) All moths equally
• (D) Moths that change colour during life

Q47. Antibiotic resistance in bacteria is an example of evolution by natural selection. How does it spread?

• (A) Bacteria learn to ignore drugs
• (B) Antibiotics change bacterial genes directly in all cells
• (C) Resistant bacteria survive treatment and reproduce, passing on resistance genes
• (D) Resistant bacteria become viruses

Q48. Fossils provide evidence for evolution. What is a fossil?

• (A) A living ancient animal
• (B) A type of rock only
• (C) A DNA sample from a museum
• (D) The remains or traces of an organism preserved in rock

Q49. Why are there gaps in the fossil record?

• (A) Because many organisms decay before fossilisation and some fossils are destroyed
• (B) Because evolution did not happen
• (C) Because fossils only form in water
• (D) Because scientists have not looked

Q50. Selective breeding involves humans choosing organisms with desired traits to breed. What is a result of selective breeding?

• (A) Increased variation in all traits
• (B) Reduced genetic diversity in the bred population
• (C) New species in one generation
• (D) Random traits only

Q51. Farmers selectively breed cows for high milk yield. What is a possible disadvantage?

• (A) Milk becomes poisonous
• (B) Cows stop producing calves
• (C) The cows may be more prone to disease due to inbreeding
• (D) Milk yield falls immediately

Q52. Biodiversity is the variety of living organisms in an area. Why is high biodiversity important?

• (A) It reduces the number of species
• (B) It increases competition only
• (C) It makes food chains shorter
• (D) It makes ecosystems more stable and resilient to change

Q53. Which human activity lowers biodiversity in an area?

• (A) Deforestation
• (B) Recycling
• (C) Creating nature reserves
• (D) Replanting forests

Q54. Deforestation for farming increases carbon dioxide in the atmosphere. Which two reasons explain this?

• (A) Trees produce carbon dioxide when cut
• (B) Fewer trees photosynthesise and burning trees releases carbon dioxide
• (C) Soil absorbs less oxygen
• (D) Farming uses less energy

Q55. Peat bogs store large amounts of carbon. What happens when peat is drained and burned?

• (A) Carbon is locked away forever
• (B) Oxygen levels rise sharply
• (C) Stored carbon is released as carbon dioxide
• (D) Nitrogen fixation stops

Q56. Global warming is linked to increased greenhouse gases. Which gas is the main one increased by burning fossil fuels?

• (A) Oxygen
• (B) Nitrogen
• (C) Hydrogen
• (D) Carbon dioxide

Q57. Methane is another greenhouse gas. Which human activity increases methane release?

• (A) Cattle farming and landfill waste decay
• (B) Photosynthesis
• (C) Wind power
• (D) Recycling paper

Q58. Which effect of global warming threatens polar species?

• (A) Warmer water increases ice
• (B) Melting ice reduces their habitat
• (C) Sea levels fall
• (D) Polar species gain more food

Q59. Acid rain is caused by sulfur dioxide and nitrogen oxides from burning fossil fuels. What damage can it cause?

• (A) It increases soil fertility greatly
• (B) It cools the climate
• (C) It damages leaves and makes lakes acidic, harming aquatic life
• (D) It increases photosynthesis

Q60. Pollution of rivers with sewage can cause a fall in oxygen levels. Why does this happen?

• (A) Sewage adds oxygen
• (B) Fish use less oxygen
• (C) Plants stop photosynthesing
• (D) Microorganisms decomposing sewage use up oxygen in respiration