Explanation:

Pollen grains are produced by male organs, anthers or stamens. www.gradeup.co 46 The formation of a pollen grain begins within the male part of a flower known as the anther, within specific tissue called sporogenic tissue. Here, the developing pollen receives nutrition and a coat of cellulose, which is a very strong plant protein. Firstly, large pollen mother cells are produced, which eventually break into individual pollen grains through a cell division. At this point, the pollen grain gets its outer coat, known as the exine, which is made from another tough plant protein. The exine protects the delicate genetic material within the pollen grain from water loss, and damage caused by Ultra Violet (UV) radiation and other environmental causes. In some plants, the pollen grain even gets a sticky outer layer to help it adhere to the female part of another plant, called the stigma. The final step involves another cell division, which forms two cells within one pollen grain. After that, the pollen grains move to a drying-out phase, after which they take on their dusty appearance and are now ready to go out into the world.