The $pH$ value of the solution in which a particular amino acid does not migrate under the influence of an electric field is called the

The $N$ atom which does not contribute to the basicity of the given compound is:

$A$ codon has a sequence of $\underline{A}$,and specifies a particular $\underline{B}$ that is to be incorporated into a $\underline{C}$. What are $\underline{A}, \underline{B}, \underline{C}$?
$\underline{A} \quad \underline{B} \quad \underline{C}$

The $pH$ at the isoelectric point of three amino acids are given as follows:

Amino acid	$pH$ at Isoelectric point
$(Amino \ acid)_{I}$	$6$
$(Amino \ acid)_{II}$	$9.8$
$(Amino \ acid)_{III}$	$3.9$

$(Amino \ acid)_{II}$ is . . . . . . ?

Amino acids are the building blocks of

Which of the following amino acids contains a heterocyclic ring in its side chain $(R)$ group?