Observation

This question was attempted by many and their performance was fair.  In part (a) candidates correctly mentioned substances found in the urine of humans.  In part (b) candidates could not state reasons why humans takes lot of water when the weather is hot.

However, the expected answers are:

5 (a)     SUBSTANCES FOUND IN THE URINE OF HUMANS

• water
• urea/uric acid/nitrogenous compound
• mineral salts
• ammonium compounds/ammonia

(b)      REASONS WHY HUMANS TAKE A LOT OF WATER DURING THE HOT WEATHER
-        to prevent dehydration/ water loss due to
-        increased thirst / demands for more water
-        increased sweating
-        increased evaporation