Haemoglobin is

Treatment of compound $O$ ($1,2-$diethylbenzene) with $KMnO_4 / H^{+}$ gives $P$ (phthalic acid),which on heating with ammonia gives $Q$ (phthalamide). The compound $Q$ on treatment with $Br_2 / NaOH$ produces $R$ ($o-$phenylenediamine). On strong heating,$Q$ gives $S$ (phthalimide),which on further treatment with ethyl $2-$bromopropanoate in the presence of $KOH$ followed by acidification,gives a compound $T$.
$(1)$ The compound $R$ is
$(2)$ The compound $T$ is
$(A)$ glycine
$(B)$ alanine
$(C)$ valine
$(D)$ serine
Identify the correct options for $(1)$ and $(2)$.

The $\alpha$-helix structure is found in:

The secondary structure of protein is stabilised by:

Which of the statements about "Denaturation" given below are correct?
$1.$ Denaturation of proteins causes loss of secondary and tertiary structures of the protein.
$2.$ Denaturation leads to the conversion of double strand of $DNA$ into single strand.
$3.$ Denaturation affects primary structure which gets distorted.

Which of the following amino acids is basic in nature?