Question

Draw a neat sketch of chloroplast.

Answer 1

Chloroplasts:

1. Chloroplasts are green-coloured plastids that are responsible for absorbing light energy and preparing food for the cell by a process known as photosynthesis. As they prepare food for the cell they are also known as the kitchen of the cells.
2. Chloroplasts contain a photosynthetic pigment known as chlorophyll.
3. Chloroplasts are flat, disc-shaped structures that measure about 2-10mm in diameter and 1mm in thickness.
4. They are made up of two membranes namely the outer membrane and inner membrane. The outer membrane permits the entry of ions and metabolites. The inner membrane is responsible for transporting proteins.
5. Both membranes are separated by a space known as intermembrane space.
6. Chloroplast consists of two regions namely stroma and grana. The fluid present inside the chloroplast is known as the stroma and inside the stroma, there is an inter-connecting membrane compartment known as stroma lamellae. The stacks of membrane-bounded, flat disc-like structures are known as grana.
7. Each disc of grana is known as a thylakoid.
8. Stroma is the site of dark reaction and granum is the site of light reaction during photosynthesis.