What is the total number of essential amino acids?

Glycylalanine is a dipeptide of which amino acids?

Assertion : Proteins are made up of $\alpha-$ amino acids.
Reason : During denaturation,secondary and tertiary structures of proteins are destroyed.

Which of the following is manufactured from molecular nitrogen by bacteria?

In an oligopeptide named Alanyl-glycyl-phenyl-alanyl-isoleucine,the number of $sp^2$ hybridised carbons is $...........$.

Read the following statements carefully:
$(A)$ Albumin is a simple protein.
$(B)$ The amino acid alanine contains an acidic side chain.
$(C)$ Insulin is a hormone.
$(D)$ Muscles contain the protein keratin.
Point out the wrong statements in the above set of statements.