Because sunlight is needed in photosynthesis which is used to make their own food which includes water and carbon dioxide.
Why Do Plants Turn Towards The Sunlight?
If plants did not turn towards the sun they would not be able to live. They would have no food.
Leaves produce food in the form of sugar for the entire plant. The leaves contain a special green substance that enables them to do this. This substance is chlorophyll. Chlorophyll can produce only in sunlight. This food producing process is called photosynthesis which means 'putting together with sunlight'.
So we can see why plants turn their leaves toward the sunlight. Botanists say that the plant is phototropic, that it turns towards the light. Plant cells contain growth substances known as Auxins. This substance moves away from the light. When the plant is not in the light the auxins make cells on the side of the plant grow faster than the cells on the lighted side.
We do not usually think of plants as moving at all. This is because the movements of plants are usually too slow to be seen. But if you could see certain plants on a fast motion film, you could see the leaves, flowers and stems are constantly moving.
Some plants move quickly. A pumpkin, squash or cucumber vine may form a complete coil around a string support in ten minutes.
Leaves produce food in the form of sugar for the entire plant. The leaves contain a special green substance that enables them to do this. This substance is chlorophyll. Chlorophyll can produce only in sunlight. This food producing process is called photosynthesis which means 'putting together with sunlight'.
So we can see why plants turn their leaves toward the sunlight. Botanists say that the plant is phototropic, that it turns towards the light. Plant cells contain growth substances known as Auxins. This substance moves away from the light. When the plant is not in the light the auxins make cells on the side of the plant grow faster than the cells on the lighted side.
We do not usually think of plants as moving at all. This is because the movements of plants are usually too slow to be seen. But if you could see certain plants on a fast motion film, you could see the leaves, flowers and stems are constantly moving.
Some plants move quickly. A pumpkin, squash or cucumber vine may form a complete coil around a string support in ten minutes.
They turn toward the sunlight because...
They...
I WON'T TELL YOU!
They...
I WON'T TELL YOU!