F.2 Science Test Paper (Eng)

What is air made up of?
nitrogen 78%
carbon dioxide 0.03%
noble gases 1% mainly argon
water vapour(variable)
oxygen 21%

How do we oobtain energy?
we obtain energy by the respiration

How do green plants obtain energy?
They do the photosythesis to produce carbohydrates in order to obtain energy

Air made up of 78%Nitrogen, 21%Oxygen, 0.03%Carbon Dioxide,0.932%inert gas(noble gas) and variable water vapour and other gases.

We obtain energy by respiration. Respiration occurs in body cells.

Oxygen + food -----respiration-----> Carbon dioxide + water.


Green plants obtains energy by photosynthesis. During photosynthesis, green plants produce food for themselves. The food is stored in the from of starch.
Carbon dioxide + water ---light energy + chlorophll---> starch + oxygen.