Master GCSE Biology

Question 1 (Knowledge Recall, 1 mark):

Q1. Name the green pigment in plants that traps light energy for photosynthesis.

Mark Scheme 1 (MS1):

- Chlorophyll (1)

Question 2 (Application, 2 marks):

Q2. Explain how photosynthesis depends on the availability of light intensity.

Mark Scheme 2 (MS2):

- As light intensity increases, the rate of photosynthesis increases up to a plateau (1)

- This is because more light energy is available for the reactions (1)

Question 3 (Extended Response, 3 marks):

Q3. Describe the differences between aerobic and anaerobic respiration. Give an example of a life process that uses each type of respiration.

Mark Scheme 3 (MS3):

- Aerobic respiration: Requires oxygen, produces more ATP (1)

- Example: cellular respiration in muscle cells during exercise

- Anaerobic respiration: Does not require oxygen, produces less ATP (1)

- Example: fermentation in yeast during bread-making (1)

Question 4 (Knowledge Recall, 1 mark):

Q4. What is the end product of fermentation?

Mark Scheme 4 (MS4):

- Lactic acid/ethanol (1)

Question 5 (Application, 2 marks):

Q5. Explain why fermentation can produce an oxygen debt.

Mark Scheme 5 (MS5):

- Without oxygen, anaerobic respiration produces lactic acid (1)

- This acid accumulates in muscles, causing pain and fatigue (1)

Question 6 (Extended Response, 4 marks):

Q6. Describe the role of limiting factors in photosynthesis. Give real-world examples of how these factors can limit the rate of photosynthesis in different environments.

Mark Scheme 6 (MS6):

- Limiting factors: Light intensity, carbon dioxide concentration, temperature (1)

- Real-world examples:

- Light intensity: Shading from trees in a forest (1)

- Carbon dioxide concentration: Low levels in polar regions (1)

- Temperature: Too high or too low temperatures can slow down or stop photosynthesis (1)

Question 7 (Knowledge Recall, 1 mark):

Q7. What is the overall chemical equation for photosynthesis?

Mark Scheme 7 (MS7):

Question 8 (Application, 2 marks):

Q8. Explain how metabolism is linked to bioenergetics.

Mark Scheme 8 (MS8):

- Metabolism refers to all chemical reactions in living things (1)

- Bioenergetics focuses on the energy transformations involved in metabolism (1)

Question 9 (Extended Response, 3 marks):

Q9. Describe the process of photorespiration in plants. Explain why it is considered a wasteful process.

Mark Scheme 9 (MS9):

- Photorespiration: Uses light energy to consume oxygen and release carbon dioxide (1)

- Wasteful because it competes with photosynthesis for resources, reducing plant growth (1)

Question 10 (Knowledge Recall, 1 mark):

Q10. What is the main source of energy for cells?

Mark Scheme 10 (MS10):

- Glucose (1)