Question

Why are pollen grains well preserved as fossils?

Answer 1

Hint: Each pollen grain is a tiny body of diverse shape and structure that forms in the male structures of seed-bearing plants and is transferred to the female structures by various mechanisms such as wind, water, insects, and so on. Pollen is produced by the anthers of the stamens in flowers in angiosperms.

Complete answer:
Pollen grains are minute structures with a variety of sizes and shapes. Pollen grains vary in size depending on the species. Pollen grains are generally between three and two hundred micrometres or microns in size.
Pollen grains are made up of three components:
During fossilisation, the inside of the cell, which is filled with living cytoplasm, deteriorates rapidly.
The inner layer of the cell wall, intine, is made up of cellulose and pectin. The intine, like the cytoplasm, destroys fast during fossilisation.
Exine, the cell wall's outer layer, is mostly made up of sporopollenin. It is one of the most durable materials. It's an N-free polymeric molecule that belongs to the terpene family of chemical chemicals.
One of the most chemically inert biological polymers is sporopollenin. It's a key component of plant spores and pollen grains' robust outer (exine) walls. It has a chemical stability that allows it to survive in soils and sediments. Because of the presence of sporopollenin, pollen grains are highly preserved as fossils.

Note:
Pollen grains are often spherical, ovule-shaped, triangular, disc-shaped, or bean-shaped, having a smooth to spiky feel. Pollen grains are naturally white in colour, though this might change depending on the plant type. Some are yellow, orange, or cream in colour, and so forth.