Total marks: 100 · Duration: 105 minutes · Tier: Foundation
Instructions to candidates
- Use black ink or black ball-point pen. Draw diagrams in pencil.
- Answer all questions in the spaces provided.
- In all calculations, show clearly how you work out your answer.
- You may use a calculator.
- For multiple-choice parts, choose one answer, A, B, C or D.
- Where a question describes apparatus or a diagram in words, you may find it helpful to sketch it.
Information
- The maximum mark for this paper is 100.
- The marks for questions are shown in brackets.
- You are expected to use good English and to organise information clearly, especially in questions marked with an asterisk (*).
- This paper covers AQA GCSE Biology topics 4.5 to 4.7: homeostasis and response; inheritance, variation and evolution; and ecology.
Paper
Question 1 — The nervous system (12 marks)
(a) Put these parts of a reflex arc in the order in which an impulse passes through them: motor neurone, receptor, relay neurone, effector, sensory neurone. [2 marks]
(b) Which of these is an effector? [1 mark]
A the retina B a muscle C the spinal cord D a sensory neurone
(c) Give two features of a reflex action. [2 marks]
(d) A student uses the ruler-drop test to measure her reaction time. Her results are 0.25 s, 0.22 s, 0.24 s, 0.29 s and 0.20 s.
(i) Calculate her mean reaction time. [2 marks]
(ii) She then drinks a cola that contains caffeine and repeats the test. Her mean reaction time is 0.19 s. What can she conclude? [1 mark]
(iii) Give two variables she should keep the same when repeating the test. [2 marks]
(iv) Why should she do each test several times? [1 mark]
(e) Name the gap between two neurones. [1 mark]
Question 2 — Hormones (12 marks)
(a) Hormones are carried around the body in the blood. Which gland produces each hormone?
(i) Insulin [1 mark]
(ii) Adrenaline [1 mark]
(iii) Testosterone [1 mark]
(b) Give two differences between nervous responses and hormonal responses. [2 marks]
(c) Describe what happens in the body when the blood glucose level rises after a meal. [2 marks]
(d) Give one difference between Type 1 and Type 2 diabetes. [1 mark]
(e) Name the hormone that causes an egg to be released from an ovary each month. [1 mark]
(f) Give one advantage and one disadvantage of using the contraceptive pill. [2 marks]
(g) Give one non-hormonal method of contraception. [1 mark]
Question 3 — Homeostasis (8 marks)
(a) What is homeostasis? [1 mark]
(b) Give two conditions in the body that are controlled by homeostasis. [2 marks]
(c) Name the part of the brain that monitors body temperature. [1 mark]
(d) Describe two ways the body cools down when it is too hot. [2 marks]
(e) Explain why it is important for the body to keep its temperature at about 37 °C. [2 marks]
Question 4 — Reproduction and DNA (10 marks)
(a) Give two differences between sexual and asexual reproduction. [2 marks]
(b) (i) Name the type of cell division that makes gametes. [1 mark]
(ii) A human body cell has 46 chromosomes. How many chromosomes are in a human egg cell? [1 mark]
(c) Which of these is the correct order of size, from largest to smallest? [1 mark]
A gene, chromosome, nucleus B chromosome, nucleus, gene C nucleus, chromosome, gene D nucleus, gene, chromosome
(d) What is a gene? [2 marks]
(e) DNA is described as a double helix. What does this mean? [1 mark]
(f) Give two reasons why scientists studied the human genome. [2 marks]
Question 5 — Inheritance (12 marks)
Cystic fibrosis is caused by a recessive allele (f). The dominant allele (F) does not cause cystic fibrosis.
(a) What is meant by a recessive allele? [1 mark]
(b) Two parents are both carriers. Their genotype is Ff.
(i) Complete a Punnett square to show the possible genotypes of their children. [2 marks]
(ii) What is the probability that a child will have cystic fibrosis? [1 mark]
(iii) What is the genotype of a child who has cystic fibrosis? [1 mark]
(c) Use the words homozygous and heterozygous to describe the genotypes FF and Ff. [2 marks]
(d) A person's sex is decided by their sex chromosomes.
(i) Give the sex chromosomes of a female. [1 mark]
(ii) Explain why there is an equal chance of a baby being a boy or a girl. [2 marks]
(e) Give one reason for and one reason against screening embryos for cystic fibrosis. [2 marks]
Question 6 — Variation and evolution (12 marks)
(a)* Some bacteria are resistant to antibiotics. Describe how a population of bacteria can become resistant to an antibiotic. [6 marks]
(b) Farmers use selective breeding to produce cows that give more milk. Describe how. [3 marks]
(c) Give one example of a genetically modified organism and the useful feature it has been given. [1 mark]
(d) What can fossils tell us about the history of life on Earth? [1 mark]
(e) Give one reason why a species may become extinct. [1 mark]
Question 7 — Classification (6 marks)
(a) The scientific name of the lion is Panthera leo.
(i) Which part of the name is the genus? [1 mark]
(ii) Name the system of naming organisms with two names. [1 mark]
(b) Put these groups in order from largest to smallest: species, kingdom, genus, class. [2 marks]
(c) In the three-domain system, name the domain that includes all plants, animals and fungi. [1 mark]
(d) What does an evolutionary tree show? [1 mark]
Question 8 — Organisms and their environment (14 marks)
(a) In a food chain: grass → rabbit → fox
(i) Name the producer. [1 mark]
(ii) Name the secondary consumer. [1 mark]
(iii) What do the arrows in a food chain show? [1 mark]
(b)* Describe how a student could use quadrats to estimate the number of daisies on a school field. [6 marks]
(c) A student found a mean of 4 daisies per quadrat. Each quadrat has an area of 1 m². The field has an area of 500 m². Estimate the number of daisies on the field. [2 marks]
(d) Give one abiotic factor and one biotic factor that can affect where daisies grow. [2 marks]
(e) Describe one way a camel is adapted to living in a hot desert. [1 mark]
Question 9 — Biodiversity and human impact (14 marks)
(a) What is biodiversity? [1 mark]
(b) Give two processes in the carbon cycle that release carbon dioxide into the air. [2 marks]
(c) Name the process in the carbon cycle that removes carbon dioxide from the air. [1 mark]
(d) Give two reasons why large areas of tropical forest are cut down. [2 marks]
(e) Give two effects of deforestation on the environment. [2 marks]
(f) Name two greenhouse gases. [2 marks]
(g) Give two possible effects of global warming. [2 marks]
(h) Give two ways of protecting biodiversity. [2 marks]