Download Revision quiz for nutrition and digestion for IGCSE Biology

Revision quiz for nutrition and digestion for IGCSE Biology
NB, where there are () parentheses, the word is optional; where there are /
slashes, you only needed to write one of the alternatives
1. What is peristalsis and where does it happen?
(2)
- The movement of food by (circular) muscle (contraction) in the
oesophagus/small intestine/large intestine
2. Which enzyme does saliva contain, and what substance does it break
down?
(2)
- Amylase, breaks down starch (into maltose)
3. What does the stomach do?
(3)
- (hydrochloric/stomach) acid kills bacteria
- Food is churned/pummelled (to increase surface area)
- Pepsin/protease: (begins the) digestion of protein
4. What does the pancreas produce?
(3)
- Amylase, protease, lipase
5. Define digestion
(2)
- Breaking down large insoluble molecules into small, soluble ones (that we
can absorb)
6. How is the small intestine adapted for efficient absorption
(3)
- It has a large surface area because it is: (1 or more of) long, folded and
has villi and microvilli
- Short distance for diffusion because it has a thin wall
- (it has blood vessels close the surface to provide a concentration
gradient)
7. What does bile do and which organ produces it?
(3)
- splits up/emulsifies lipids (to increase their surface area)
- Neutralizes (stomach) acid so digestive enzymes work at optimum pH
8. Name two important minerals and state their role in the body.
(4)
- iron to produce haemoglobin (in red blood cells)
- Calcium to build strong bones (and teeth)
9. What does the large intestine do?
(1)
- (re)absorbs water
10. How do different temperatures affect enzymes?
- Low temperature: they work slowly
- Optimum temperature: work fastest
- High temperature: are denatured (so stop working)
(3)