Question

Match the following:

$\begin{array}{cc}\text{Column~I}& \text{Column~II}\\ \text{(i) Haemoglobin}& \text{(1) Fibrous protein}\\ \text{(}ii)Keratin& \text{(2) Non-essential}\\ \text{(iii)Glycine}& \text{(3)}\alpha \text{2}\beta \text{2}\\ \text{(iv)Valine}& \text{(4) Essential}\end{array}$

• A. i-3, ii-1, iii-2, iv-4
• B. i-2, ii-3, iii-4, iv-1
• C. i-1, ii-2, iii-3, iv-4
• D. i-3, ii-1, iii-4, iv-2

Answer 1

The correct option is A i-3, ii-1, iii-2, iv-4

Haemoglobin is an iron-containing pigment protein that gives blood its red colour. It exists in a quaternary structure composed of two $\alpha$- chains and two $\beta$ -chains $\left(\alpha 2\beta 2\right)$.

Keratins are fibrous proteins present in eukaryotes. They can occur as helical ⍺-keratin or $\beta$-keratin. In vertebrates, almost the entire dry weight of hair, wool, feathers, nails, horns, hooves and the majority of the outer skin layer occur as $\alpha$-keratin.

Glycine is the simplest amino acid where the R group is hydrogen. It is a non-essential amino acid as it can be synthesised by the body.

Valine is an aliphatic essential amino acid in humans.