Rocket peers at his growing bean. "It never eats a single snack," he says. "So how does it grow?"
Raven looks at the leaves facing the window. "What do you notice about which way they point?"
Nova hovers in a sunbeam. "Plants are cooks," she says. "Look for their kitchen and their stove."
Rocket grins. "Is the stove the Sun?"
Animals have to eat food. Plants make their own food.
Plants make food in a process called photosynthesis.
A plant needs three things for it: light, water and carbon dioxide.
Carbon dioxide is a gas in the air.
The plant uses light energy to turn water and carbon dioxide into sugar.
It gives off oxygen as a leftover.
| Goes in | Comes out |
|---|---|
| light energy | sugar (food for the plant) |
| water (from the soil) | oxygen (into the air) |
| carbon dioxide (from the air) |
If light, water or carbon dioxide is missing, photosynthesis stops.
Most of the time, more light means more photosynthesis, up to a limit.
| Statement | True or false? |
|---|---|
| Plants make their own food. | ? |
| Photosynthesis needs light, water and carbon dioxide. | ? |
| Plants give off carbon dioxide as a leftover of photosynthesis. | ? |
| Without light, photosynthesis stops. | ? |
Brilliant food science! Tomorrow we solve a very old mystery about where a tree's weight comes from.