The functional group which is found in amino acid is

Glycylalanine is a dipeptide of which amino acids?

Thyroxine produced in the thyroid is an iodinated derivative of . . . . . . amino acid.

Enlist the points of difference between fibrous and globular proteins.

Assertion: $\alpha$-amino acids exist as internal salt in solution as they have amino and carboxylic acid groups in near vicinity.
Reason: $H^{+}$ ion given by carboxylic group $(-COOH)$ is captured by amino group $(-NH_2)$ having lone pair of electrons.

In the given pentapeptide, find out an essential amino acid $(Y)$ and the sequence present in the pentapeptide: Choose the correct answer from the options given below: