Question 2
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In the table below, name five classes of food provided for human consumption, one importance of each class in the diet and one example of each class.
Food class
One importance
One example
[15 marks]
(b) Explain briefly how insulin regulates the amount of glucose in the blood. [5 marks]
Observation
Candidates lost marks to their inability to spell the food classes and examples of food classes properly.
A few candidates were able to explain how insulin regulates the amount of glucose in blood
.
The expected answers are:
(a) Food classes provided by plants and examples
Food class |
One importance |
One example |
Carbohydrate |
Source of energy/starting point |
Starch/corn/cassava/maize/yam/rice/millet |
Roughage |
For digestion/bowel |
Cereals/citrus/vegetables/fruits |
Proteins |
For growth and |
Beans/peas/groundnut/soya beans |
Fats and |
Source of energy/energy |
Groundnuts/soya beans/palm fruit/shea |
Vitamins |
For health/immunity/growth |
Citrus fruits/vegetables/carrots/red |
Mineral salts |
For general metabolism/growth |
Vegetables/fruits/tiger nuts/plantain/banana |
15 x 1[15 marks]
Note: Spellings of the food class must be correct to score.
(b) Regulation of blood glucose by insulin
- when the level of glucose in the blood rises;
- insulin is secreted;
- from the pancreas/islets of Langerhans;
- insulin stimulates liver/fat/muscles to metabolise glucose;
- to glycogen;
- promotes build-up of fats and proteins;
- inhibits their use as energy;
- leading to lowering of the level of glucose in the blood.