Amino acids and proteins

The structure of a peptide is given below.

If the absolute values of the net charge of the peptide at pH = 2, pH = 6, and pH = 11 are $|z_1|$, $|z_2|$, and $|z_3|$, respectively, then what is $|z_1| + |z_2| + |z_3|$?

Among the following, the essential amino acid is :

The compound T is

Thiol group is present in :

Consider the following sequence for aspartic acid :

The pI (isoelectric point) of aspartic acid is :

Observation of "Rhumann's purple" is a confirmatory test for the presence of :

The major product of the reaction is

The total number of distinct naturally occurring amino acids obtained by complete acidic hydrolysis of the peptide shown below is

A tetrapeptide has -COOH group on alanine. This produces glycine (Gly), valine (Val), phenyl alanine (Phe) and alanine (Ala), on complete hydrolysis. For this tetrapeptide, the number of possible sequences (primary structures) with $\ce{-NH2}$ group attached to a chiral center is

The substituents $\mathbf R_1$ and $\mathbf R_2$ for nine peptides are listed in the table given below. How many of these peptides are positively charged at pH = 7.0?

$$\ce{H3N+-CH(H)-CO-NH-CH(R1)-CO-NH-CH(R2)-CO-NH-CH(H)-COO-}$$

Peptide	$\mathbf R_1$	$\mathbf R_2$
I	H	H
II	H	$\ce{CH3}$
III	$\ce{CH2COOH}$	H
IV	$\ce{CH2CONH2}$	$\ce{(CH2)4NH2}$
V	$\ce{CH2CONH2}$	$\ce{CH2CONH2}$
VI	$\ce{(CH2)4NH2}$	$\ce{(CH2)4NH2}$
VII	$\ce{CH2COOH}$	$\ce{CH2CONH2}$
VIII	$\ce{CH2OH}$	$\ce{(CH2)4NH2}$
IX	$\ce{(CH2)4NH2}$	$\ce{CH3}$

A decapeptide (Mol. Wt. 796) on complete hydrolysis gives glycine (Mol. Wt. 75), alanine and phenylalanine. Glycine contributes 47.0 % to the total weight of the hydrolysed products. The number of glycine units present in the decapeptide is

The total number of basic groups in the following form of lysine is

Match the chemical substances in Column I with type of polymers/type of bonds in Column II. Indicate your answer by darkening the appropriate bubbles of the 4 × 4 matrix given in the ORS.