Assertion: The amino acid Glycine comes under the category of non-essential amino acids.
Reason: This is due to the fact that it cannot be synthesised in the body.
A. Both Assertion and Reason are Correct and Reason is the Correct explanation for Assertion
B. Both Assertion and Reason are Correct and Reason is not the Correct explanation for Assertion
C. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect

Answer Verified Verified
Hint: Glycine (Gly), which is one of the common amino acids, has no side-chain.
It can be synthesized from the amino acids serine and threonine and from other sources. They do not require dietary sources.

Complete answer:
In general, glycine is frequently located on the protein surface inside loop or coil regions (without specified secondary structure) offering high versatility for the polypeptide chain at these locations. This means it should be quite hydrophilic.
Proline, on the other hand, is typically non-polar and has opposite properties to those of Gly, it gives the polypeptide chain rigidity by placing certain angles of torsion on the structure section.

Biosynthesis- Glycine is not necessary for a human diet, because it is biosynthesized in the body from the amino acid serine, which in effect is extracted from 3-phosphoglycerate, but the metabolic ability of glycine biosynthesis does not fulfill the requirement for collagen synthesis.
In most animals, the enzyme serine hydroxymethyltransferase catalyzes this process through the cofactor pyridoxal phosphate.

 So, the option (C) is correct

Note: Glycine is part of a number of non-essential mammalian amino acids. They can also be synthesized from amino acids like threonine and serine, and from other origins as well. They don't need any type of dietary sources.
Serine + Tetrahydrofolate → Glycine + $N_5$, $N_{10}$ -Methylene tetrahydrofolate + $H_2O$
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