Animals eat to get food, but green plants make their own food. The process plants use is called photosynthesis. We say that plants can photosynthesise.
These are the things that plants need for photosynthesis:
- carbon dioxide
- water
- light
These are the things that plants make because of photosynthesis:
We can show photosynthesis as this word equation:
carbon dioxide water (+ light energy) glucose oxygen
(Light energy is shown in brackets because it is not a substance.)
This is the symbol equation for photosynthesis:
Where does this process take place in the plant?
Photosynthesis takes place in the chloroplasts in plant cells. Chloroplasts contain a green substance called chlorophyll. This absorbs the light energy needed to make photosynthesis happen. Plants can only photosynthesise in the light.
Palisade cells in leaves have lots of chloroplasts
Plants get carbon dioxide from the air through their leaves, and water from the ground through their roots.
Light energy comes from the sun.
The glucose produced can be turned into other substances, such as starch, which is used for storage. The oxygen produced is released into the air from the leaves.
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