Question

Abundant occurrence of fossilized pollen grains is due to resistant:
A. Lignocellulose
B. Sporopollenin
C. Pectin Cellulose
D. Pectoligin

Answer 1

Hint: Due to the hard covering of Sporopollenin that makes the outer wall of the pollen grain, exine, a large number of fossilized pollen grains are found during the excavation process of older parts. No known enzyme can hydrolyze this substance.
Step by step solution:
One of the most chemically inert biological polymers seems to be sporopollenin. It contributes significantly to plant spores and pollen grains' hard outer (exine) walls. It has high chemical stability and is usually well-preserved in soils and sediments. The exine layer is frequently intricately sculpted in species-specific patterns, allowing palynologists to learn about past plant and fungal populations from content recovered from (for instance) lake sediments.
Spores are dispersed by a variety of environmental factors, including wind, water, and animals. Seeing as sporopollenin is resistant to chemical degradation by organic and inorganic chemicals, the sporopollenin-rich walls of pollen grains and spores can remain in the fossil record for hundreds of millions of years under the right conditions.
The extremely resistant nature of the pollen grains' outer wall accounts for their abundant occurrence and preservation. This is the exine wall, which is made up of a compound known as sporopollenin. It is formed as a result of the polymerization of carotenoids and carotenoid esters.
In various proportions, lignocellulose is composed primarily of cellulose, hemicelluloses, and lignins. Wood as well as agricultural wastes, such as straw and sugar cane bagasse, represent the most important lignocellulosic materials.
Hence, The correct option is B.

Note: Pectin Cellulose is a type of cellulose found in fibres such as flax fibre and the stems of Gramineae plants. In lignified tissues, lignocellulose can be found. It can be found in jute fibres. It is the dry mass of the plant and is among the most abundant raw materials utilized in the production of ethanol, a biofuel.