Structure of the plant cell chloroplast
- These are organelles found in plant cells and algal cells.
- They are oval-shaped.
- They are made up of two surface membranes, i.e., outer and inner membranes, and an inner layer known as the thylakoid layer has two membranes.
- The outer membrane forms the external lining of the chloroplast, while the inner membrane is below the outer layer.
- The membranes are separated by thin membranous space, and within the membrane, there is also a space known as the stroma. The stroma houses the chloroplast.
- The third layer, known as the thylakoid layer, is extensively folded, making the appearance of a flattened disk known as thylakoids which have large numbers of chlorophyll and carotenoids and the electron transport chain, defined as the light-harvesting complex, used during photosynthesis.
- Thylakoids are piled on top of each other in stacks known as grana.
Functions of the plant cell chloroplast
- The chloroplast is the site of food synthesis for plant cells, by a mechanism known as photosynthesis.
- Chloroplasts contain chlorophyll, a green pigment that absorbs light energy from the sun for photosynthesis.
- The photosynthesis process converts water, carbon dioxide, and light energy into nutrients for plant utilization.
- Thylakoids contain chlorophyll pigments and carotenoids for trapping light energy for photosynthesis.
- The chlorophyll pigment gives plants their green color.