Leaf Structure and Photosynthesis

Science, Grade 6


Table Of Contents: Leaf Structure and Photosynthesis

1. Where Does Photosynthesis Occur?
Photosynthesis primarily occurs in the plant leaves.
2. Chloroplasts
The entire process takes place in an organelle called the chloroplast. Inside each chloroplast there are green pigment molecules called chlorophyll.
3. Chlorophyll
Chlorophyll absorbs light energy from the sun. This pigment gives plants their green color.
4. Water Movement to the Leaves
The water needed for photosynthesis travels to the leaves through the plant's vascular system. Leaf veins deliver the water to the chloroplasts.
5. Leaf Stomata and Carbon Dioxide
Carbon dioxide needed for photosynthesis enters the leaf through tiny pores called stomata (singular stoma) found on the underside of the leaf.
6. Guard Cells Respond to the Environment
Each stoma is made up of a pair of cells called guard cells. These cells change size in response to the environment, causing the pore to open or close.
7. Pore Is Open in Daylight
The pore is usually open during the daylight, when photosynthesis occurs.