Plants feed us, but how do plants get fed?
Things Required:
A stalk of celery with its leaves
1 teaspoonful of red food colouring
A half glass of water
Directions:
Stand the stalk of celery in a half glass of water coloured with a teaspoonful of food colouring. Start it off in bright light and let it remain overnight.
This Is What Happens:
The leaves turn reddish.
Science Behind It:
The celery stalk is the stem of the celery plant. It absorbs water and minerals from the soil through its root hairs by means of osmosis. Osmosis is a process by which some liquids and gases pass through a membrane—a kind of skin. The water passes into nearby cells and is carried up through its centre tubes to the stem and leaves of the plant.
The chlorophyll in the leaves—their green colouring—turns the light of the sun into energy. This energy is used to combine some of the water from the soil with carbon dioxide from the air. The carbon and oxygen of the carbon dioxide react with the hydrogen and oxygen of the water to form carbohydrates. This sugar and starch serve as food for the plant—and eventually for us.
