The answer is hard tissue.
Usually, hard tissue, such as bones and teeth or exoskeleton is much more preserved than soft tissue (organs, skin, etc.). Fossils become fossils by a process of mineralization. Hard tissues are more mineralized during life than organs. So it is no surprise that hard tissues take part in the process of mineralization and is preserved in fossils, unlike soft tissues.
Fatty acids only
Acetyl coenzyme A is a biological molecule that is used in biochemical reactions. These biochemical reactions include the breakdown or hydrolysis of protein, carbohydrates and lipid molecules. The hydrolysis of these molecules in the presence of acetyl CoA produces energy and its primary function is fatty acid metabolism.
It is known as a transgenic organism. This procedure is otherwise called "genetic engineering." Genes of one species can be altered, or qualities can be transplanted starting with one animal types then onto the next. Genetic engineering is made conceivable by recombinant DNA innovation. Living beings that have modified genomes are known as transgenic.