Question

The main constituent of the intine layer of the pollen grain is ______.

Options

• Sporopollenin

• Pectocellulose

• Lignin

• Lignopectin

Answer 1

The main constituent of the intine layer of the pollen grain is pectocellulose.

Explanation:

The intine layer of the pollen grain is mainly composed of pectin and cellulose (together called pectocellulose). This layer lies beneath the exine and plays a role during pollen germination by forming the pollen tube. The exine, on the other hand, is made of sporopollenin, which is highly resistant and protective but not part of the intine. Thus, the intine’s main constituent is pectocellulose, not sporopollenin or lignin-based compounds.