Question

Pollen grains have been found well-preserved in fossil. Choose the statement that gives the correct explanation.

• A. Intine is made of cellulose and pectins
• B. Germ pores were closed to avoid entry of water
• C. Exine is made up of sporopollenin
• D. Pollen grains form a cyst during unfavourable conditions

Answer 1

The correct option is C Exine is made up of sporopollenin

Pollen grains have been found to be well-preserved as fossils because of the tough exterior. The outer wall of pollen, called exine, is made up of a highly resistant organic material called sporopollenin.

Sporopollenin is able to withstand high temperatures and strong acids and alkali. It cannot be degraded by any natural enzyme known so far.

Intine or the inner wall is made of cellulose and pectin. But this doesn't make it tough to withstand the extreme conditions of preservation.

Pollen grains neither undergo encystation nor close the germ pores to prevent decay.