Question 1
Supplement (what this means)
Supplement: only for the Extended papers (2 and 4). Core students can skip it. What the labels meanWhich shows the products of the digestion of fats and oils by lipase?
- Amino acids
- Fatty acids and glycerol
- Simple reducing sugars
- Maltose and glucose
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Answer: B
Question 2
(a) Describe what is meant by chemical digestion. [2] (b) Explain why the products of chemical digestion can be absorbed into the blood. [1]
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- (a) breakdown of large molecules (1)
- insoluble molecules into small soluble molecules (1)
- (b) they are small and soluble / can pass through the gut wall (1)
Question 3
Supplement (what this means)
Supplement: only for the Extended papers (2 and 4). Core students can skip it. What the labels meanComplete the table for the three digestive enzymes.
| Enzyme | Substrate | Product | Where secreted |
|---|---|---|---|
| Amylase | |||
| Protease | |||
| Lipase |
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- amylase: starch (1)
- amylase: simple (reducing) sugars (1) allow maltose; ignore sugar unqualified
- amylase: salivary glands / pancreas (1)
- protease: protein and amino acids (1)
- protease: stomach / pancreas (1)
- lipase: fats and oils and fatty acids and glycerol (1)
- lipase: pancreas (1)
- Max 6
Question 4
Supplement (what this means)
Supplement: only for the Extended papers (2 and 4). Core students can skip it. What the labels meanDescribe two functions of hydrochloric acid in gastric juice.
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- kills harmful microorganisms / bacteria in food (1)
- provides an acidic pH for optimum enzyme (protease / pepsin) activity (1)