Question

Write the composition of intine and exine layers of a pollen grain.

Hint:

The exine's strong and durable sporopollenin protects the pollen grain during its transport, while the intine aids in the development of the pollen tube for fertilization.

Answer 1

Composition of intine and exine layers of a pollen grain:
- Exine layer:
- The exine is the outermost layer of the pollen grain. It is composed of a complex substance called sporopollenin, which is highly resistant to degradation.
- Sporopollenin is made of biopolymeric compounds like lipids and phenolic compounds and gives the pollen grain its rigidity and protection against environmental stress.
- Intine layer:
- The intine is the inner layer of the pollen grain and is mainly composed of cellulose and pectin.
- It is more flexible than the exine and allows for the formation of the pollen tube during fertilization.