Q.20. A portion of the cross-section of a leaf is shown in the diagram. Answer the following.
i. Label 1 to 4
ii. What kind of anatomy is shown in the diagram?
iii. Write the structure and function of 2 and 4.
Please find below the solution to the asked query
The labelling is not correctly visible due to unclear diagram. However, I am providing answer based on my own understanding.
- Mesophyll cells
- Bundle sheath cells
- Chloroplasts with large starch granules
Structure and function of chloroplasts labelled 2.
Structure: Chloroplasts are disc-shaped organelles enclosed by a double membrane. A chloroplast has two distinct regions—grana and stroma.
Grana are the stacks of flattened discs containing chlorophyll molecules. These molecules are responsible for the production of food through photosynthesis. The inner membrane of the chloroplast encloses the protein-rich fluid-like ground substance known as stroma. Stroma is the homogeneous mixture in which the grana are embedded.
Thylakoids usually lie in stacks (like coins in piles) called grana.
Function: They are the main sites of photosynthesis.
Structure and function of chloroplasts with large starch granules labelled 4.
They are double membranous structures arranged concentrically. They have large starch granules and unstacked thylakoid membranes.
They help in Calvin cycle, synthesis and storage of starch etc.
Hope this information clears you doubt about the topic.