Question 7
(a)(i) List the components of fat. [2 marks]
(ii) Outline three functions of fat. [3 marks]
(b) State two functions of sodium in humans. [2 marks]
(c) State three importance of vitamin A. [3 marks]
Observation
Many candidates attempted this question and their performance was poor. In part (a) many candidates answered it wrongly, some listed vitamins A,B,D,E&K. In part (b) many candidates could not outline functions of fat correctly. In part (c) some candidates wrote importance of vitamin C instead of vitamin A.
The expected answers are as follow:
(a) (i) Composition of fat
- carbon;
- hydrogen;
- oxygen .
(ii) Functions of fat
- provision of energy;
- solvent for fat soluble vitamins;
- component of cell membrane;
- prevent loss of heat from the body/act as an insulator;
- protect certain vital organs.
(b) Functions of sodium
- regulates fluid balance of the body;
- transmission of impulses in nerve cells and muscles;
- for cell membrane permeability;
- maintain blood volume/blood circulation.
(c) Importance of Vitamin A in Humans
- improves vision/prevent night blindness;
- increases resistance to disease;
- for cell growth/development;
- maintains the skin;