Question

Intine layer of the pollen grain is made up of
A)Inner cellulose, outer pectin
B)Outer cellulose, inner pectin
C)Only with cellulose
D)Only with pectin

Answer 1

Hint:In the process of formation of male reproductive part of the plants the microspore undergo cell division that form four haploid microspores and this microspore further falls on stigma and undergo fertilization.

Complete answer
To answer this question, we have to know about the pollen grains. The pollen grains are the reproductive part of the plants that are found in the anther. They are produced in the microsporogenesis process. From each diploid sporogenous cell four microspores are produced during meiotic division.
Once the four microspores get formed the wall of the pollen grains starts developing that contains callose walls. The pollen grains have three different parts; the center consists of the cytoplasmic part that is the source of nuclei involved in the fertilization process. The cytoplasm is surrounded by the plasma membrane, the pollen grains composed of vegetative cells as well as generative cells when matured. The vegetative cells are larger in size and have large amounts of food in stored form while the generative cells are smaller and float in the cytoplasm of the vegetative cell. Inside the pollen gain, it has one generative nucleus and one tube nucleus; the generative nucleuses when get divided two male gametes are formed and develop the pollen tube after pollination.
Now, the wall of the pollen grain consists of an inner layer that is the intine and an outer layer that is the exine. The intine is composed of cellulose and hemicellulose and the exine is made up of sporopollenin that is resistant against high temperature, alkali, strong acid, and enzyme. Therefore, we concluded that the intine layer of the pollen grains consist of both pectin and cellulose.

Hence, the correct answer is ‘B’. outer cellulose, inner pectine.

Note:In some plants the pollen grains contain sharp teeth like projection that involve in the adhering process of pollen grains to the surface of stigma or else it may get dispersed into the ground rather than the pollen tube.