Question

Draw the structure of chloroplast and label the parts.

Answer 1

Hint: Chloroplasts are membrane bound plastids that contain a network of membranes embedded into liquid matrix and contain chlorophyll which imparts green color to plants and helps in photosynthesis.

Complete answer:

Following are the parts of chloroplast:
1) Envelope or outer membrane- semi-porous in nature and permeable to small molecules and ions but it is not permeable to larger proteins.
2) Intermembrane space- it is a thin space of 10-20 nanometers which is present between the outer and inner membrane of chloroplast.
3) Inner membrane- it forms a border to the stroma. It helps in regulating the passage of materials in and out as well as regulates the fatty acids and lipids also synthesized in this membrane.
4) Stroma- it is an alkaline, aqueous fluid which is present within the inner membrane of the chloroplast. Space outside the thylakoid space is known as stroma.
5) Thylakoid system- it is suspended in the stroma. This system is a collection of membranous sacs known as thylakoids. They are arranged in stacks called grana. Each granum contains 10-20 thylakoids.
6) Peripheral reticulum- chloroplasts of some plants contain an additional set of membranous tubules known as peripheral reticulum which originates from the inner membrane. Tiny vesicles bud off from the inner membrane and form the tubules of the peripheral reticulum.
Note: All of the components of chloroplast participate in several functions of the cell. Chloroplasts also provide metabolic activities for plant cells.Chloroplasts are biconvex or plano convex in shape. It has different shapes like spheroid, filamentous, ovoid.