ANATOMY

Detailed explanation-1: -Early primates happened to have a gene that made it possible to create their own vitamin C. Due to evolution later primates, including humans, have lost this gene.

Detailed explanation-2: -Vitamins are organic compounds which have to be obtained from the diet, either because an organism does not have the enzymes necessary to synthesize them or because it cannot produce them in sufficient quantities [1].

Detailed explanation-3: -Most plants and animals synthesize ascorbic acid for their own requirement. However, apes and humans can not synthesize ascorbic acid due to lack of an enzyme gulonolactone oxidase.

Detailed explanation-4: -Pseudogenes have been defined as nonfunctional sequences of genomic DNA originally derived from functional genes.