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2 marksNutrition in Living Organisms

CSEC Biology · January 2021 · Paper 2 · Question 1(a)

Enzymes acting as biological catalysts and an investigation into amylase activity across different pH levels.

State TWO reasons why enzymes are referred to as 'biological catalysts'.

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Other parts of this question

  1. 1(b)(i)Record the results presented on the graph in Figure 1 in a suitable table.[4 marks]
  2. 1(b)(ii)With reference to the rate of enzyme activity, suggest TWO reasons for the shape of the graph during EACH of the following pH ranges: pH 4-5 and pH 6-8.[4 marks]
  3. 1(b)(iii)Suggest ONE reason why the graph has a 'U' shape.[1 mark]
  4. 1(b)(iv)Predict how many seconds it would take for amylase to completely break down starch at pH 5.5 using the graph in Figure 1.[1 mark]
  5. 1(b)(v)Determine the optimum pH of amylase using the graph in Figure 1.[1 mark]
  6. 1(b)(vi)Predict the pH at which amylase would completely break down starch in 80 seconds.[1 mark]
  7. 1(c)With reference to Figure 1 on page 4, describe a suitable procedure that can be used to investigate the effect of pH on the time taken for amylase to digest…[5 marks]
  8. 1(d)Suggest TWO ways in which mammals can decrease the time they take to break down food molecules if the food molecule is too large.[2 marks]
  9. 1(e)Complete Table 1 by identifying the deficiency disease associated with Vitamin C and the vitamin/mineral deficient when there is abnormal clotting of the blood.[2 marks]
  10. 1(f)(i)Explain ONE way in which white blood cells defend the body against disease.[1 mark]
  11. 1(f)(ii)Explain ONE way in which platelets defend the body against disease.[1 mark]

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