Observation

This question was attempted by many candidates and their performance was fair. 
In part (a) candidates could not adequately define enzyme, they define enzyme as organic particles found in saliva.  In part (b) candidates correctly named one food nutrient-acted upon by the digestive enzymes such as trypsin, renin, lipase and amylase.

The expected answers are as follows

2 (a)     ENZYME
An enzyme is an organic catalyst, proteineous in nature, specific in action and secreted by special groups of cells in the body.                                       
(b)       FOOD NUTRIENTS ACTED UPON BY THE FOLLOWING DIGESTIVE ENZYMES
(i)         trypsin             -           protein
(ii)        renin                -           milk protein/casein/whey
(iii)       lipase               -           fat/oil/lipids
(iv)       amylase           -           carbohydrate/starch