Question

>Male gametes or sperms are developed from the generative cells by:
A. Meiotic division
B. Mitotic division
C. Amitotic division            
D. none of these

Answer 1

Hint: >Male gametes function as the reproductive cell, particularly in the pollen grain of angiosperms where they divide to produce two male gamete nuclei. The tube cells further form the pollen tube.


Step by step solution:
Generic cells create the male gametes. Four microsporangia are often found in one anther. The microsporangia create anther sacs or pollen sacs, which are sacs or pockets within the anther. One locule may form, when the two distinct locules are on either side of another fuse. Each microsporangium starts off with diploid pollen mother cells and is lined with a nutritive membrane known as the tapetum. To create haploid spores, these go through meiosis. During a tetrad, the spores might stay joined together or can separate following meiosis. The result of each microspore's subsequent mitotic division is an immature microgametophyte known as a pollen grain.
The male gametophyte is the pollen grain. The pollen grain's cell divides unevenly into two cells known as generative cells and vegetative cells. The vegetative cell supplies food. The two male gametes are created by a mitotic division of the generative cell. Together with the pollen tube, these two male gametes migrate in the direction of the female gametophyte.
The pollen tube, a tubular outgrowth from the pollen grain that houses the sperm cells within its cytoplasm, is then produced by the vegetative cell. Pollen mother cells undergo meiotic division, resulting in the production of four microspores during the process of microsporogenesis within anther.

So, option B is correct.

Note: For successful pollination to take place, angiosperm pollen must be transferred to the stigma, the receptive surface of the carpel, of a suitable flower. The pollen grain (an immature microgametophyte) normally completes its development after reaching the stigma. In order to produce two sperm nuclei, it may develop a pollen tube and go through mitosis.