Enzymes belong to which class of compounds?

Which of the following statements is false?

The one that does not stabilize $2^{\circ}$ and $3^{\circ}$ structures of proteins is

What is the $pH$ of $0.01 \ M$ glycine solution? For glycine,$K_{a1} = 4.5 \times 10^{-3}$ and $K_{a2} = 1.7 \times 10^{-10}$ at $298 \ K$.

Enlist the points of difference between fibrous and globular proteins.

Find the isoelectric point $(pI)$ of the given amino acid: $HOOC-CH_2-CH_2-CH(NH_3^+)-COOH$. Given: $pK_{a1} = 2$,$pK_{a2} = 4$,$pK_{a3} = 9$.