AQA GCSE Combined Science: Trilogy — Biology Paper 1 (Foundation Tier)

Total marks: 70 · Duration: 75 minutes · Tier: Foundation

Instructions to candidates

• Answer all questions in the spaces provided.
• You are expected to use a calculator where appropriate.
• This paper covers Topics 1–4: Cell Biology, Organisation, Infection and Response, and Bioenergetics.
• The maximum mark for this paper is 70. The marks for each question are shown in brackets.

Paper

Section A — Multiple Choice (5 marks)

For each question, choose the one correct answer.

1. Which part controls what enters and leaves an animal cell? (1 mark) A) Cell wall B) Cell membrane C) Nucleus D) Vacuole

2. Which of these is a job of the nucleus? (1 mark) A) Releases energy B) Controls the cell and holds DNA C) Makes food D) Supports the cell

3. A red blood cell carries which substance around the body? (1 mark) A) Carbon dioxide only B) Oxygen C) Glucose only D) Water only

4. Which type of microorganism causes measles? (1 mark) A) Bacterium B) Fungus C) Virus D) Protist

5. What gas is produced by photosynthesis? (1 mark) A) Carbon dioxide B) Nitrogen C) Hydrogen D) Oxygen

Section B — Structured Questions (65 marks)

6. The diagram shows an animal cell. [Diagram: an animal cell labelled with parts A (nucleus), B (cytoplasm), C (cell membrane), D (mitochondria).] (a) Name parts A and C. (2 marks) (b) Most chemical reactions happen in part B. Name part B. (1 mark) (c) Aerobic respiration takes place in part D. Name part D. (1 mark) (d) Give two parts found in a plant cell that are not found in an animal cell. (2 marks) (e) A bacterial cell does not have a nucleus. Where is its genetic material found? (1 mark)

7. A student looked at onion cells under a light microscope. (a) The real width of one cell is 0.2 mm. Convert this length into micrometres (µm). (1 mark) (b) The image of the cell is 40 mm wide. Using magnification = image size ÷ real size, work out the magnification. (2 marks) (c) Give one reason why a stain is added to the onion cells before viewing. (1 mark) (d) State one way an electron microscope is better than a light microscope. (1 mark)

8. Substances move in and out of cells. (a) Define diffusion. (2 marks) (b) Name the process by which water moves across a cell membrane. (1 mark) (c) Active transport needs energy. Give one example of active transport in plants. (2 marks) (d) Explain two ways the small intestine is adapted to absorb digested food quickly. (4 marks)

9. Enzymes are biological catalysts used in digestion. (a) Name the enzyme that breaks down starch, and name the product formed. (2 marks) (b) Bile is released into the small intestine. Give two functions of bile. (2 marks) (c) A student tested a food sample. It turned Benedict's solution brick-red when heated. What does this show is present? (1 mark) (d) Enzymes work best at a particular temperature. Explain what happens to an enzyme above about 45 °C. (3 marks)

10. Many diseases are caused by pathogens. (a) What is a pathogen? (1 mark) (b) Draw one line from each disease to the type of pathogen that causes it. (3 marks) Diseases: Malaria · Salmonella food poisoning · Rose black spot Pathogens: Bacterium · Fungus · Protist (c) Give two ways the human body stops pathogens entering through the skin and breathing system. (2 marks) (d) Describe how white blood cells defend the body against pathogens. (3 marks)

11. Plants make food by photosynthesis. (a) Complete the word equation for photosynthesis: (2 marks) carbon dioxide + water → __________ + __________ (b) State two things a plant needs for photosynthesis to happen. (2 marks) (c) A student measured the bubbles of gas given off by pondweed at different light intensities. Describe how light intensity affects the rate of photosynthesis. (2 marks) (d) Name one other factor (other than light) that can limit the rate of photosynthesis. (1 mark)

12. Cells can be specialised for their function. (a) A sperm cell has a tail. Explain how the tail helps the sperm cell do its job. (2 marks) (b) Root hair cells have a large surface area. Explain how this helps the plant. (2 marks) (c) Name the process by which body cells divide to make two identical cells. (1 mark)

13. This question is about respiration. Respiration releases energy from glucose. Describe and compare aerobic and anaerobic respiration in humans. In your answer you should include the reactants and products of each, and say which releases more energy. (6 marks)

14. A student investigated the effect of light on the rate of photosynthesis using pondweed. (a) Name the gas the student counted bubbles of to measure the rate. (1 mark) (b) Give two variables the student should keep the same. (2 marks) (c) The student moved the lamp closer to the pondweed. Describe and explain the effect on the number of bubbles produced. (3 marks) (d) Suggest why the student repeated the count at each distance. (2 marks) (e) Name the green pigment that absorbs the light needed for photosynthesis. (1 mark)