Biomolecules

Glycosidic linkage is a type of covalent bond that joins carbohydrate molecules to another group.

In lactose, the glycosidic linkage is formed between C-1 of galactose and C-4, glycosidic of glucose.

(A) Valium – (4) Tranquilizer

A tranquilizer drug became a standard drug for the treatment of anxiety and one of most commonly prescribed drugs of all time.

(B) Morphine – (3) Analgesic

Morphine is effective for both acute and chronic pain and often used before and after surgery.

(C) Norethindrone – (1) Antifertility drug

It is a form of progesterone, a female hormone important for regulating ovulation and menstruation.

(D) Vitamin B₁₂ – (2) Pernicious anaemia

It is a nutrient that helps to keep our body blood cells and nerve cells healthy and help in making DNA.

Monosaccharide oxidises on reacting with HNO₃ to form carboxylic acids. Primary alcohols also oxidise to carboxylic acid alongwith aldehyde.

Complete reaction is as follows :

Vitamins are substances that body need to grow and develop normally. As human body does not produce vitamins, it is required to take in diet.

Vitamin-B$_1$ is thiamine which is water soluble vitamin.

Vitamin-B$_2$ is Riboflavin, B$_{12}$ is cobalamine and B$_6$ is pyridoxine.

As the molecule exist in 3 states in aqueous solution, it means, it is a amino acid. Alanine is example of amino acid.

In aqueous medium alanine is exist as a Zwitter ion.

Cationic form of alanine exists in acidic medium.

Hence, Assertion is correct but Reason is incorrect.

Preparation of glucose from starch When starch is boiled with dilute sulphuric acid at 393 K under pressure 2-3 atm. It is hydrolysed to give glucose

$\underset{\text { Starch }}{\left(\mathrm{C}_6 \mathrm{H}_{10} \mathrm{O}_5\right)_n}+n \mathrm{H}_2 \mathrm{O} \underset{343 \mathrm{~K}, 2-3 \mathrm{~atm}}{\stackrel{\text { Dil. } \mathrm{H}_2 \mathrm{SO}_4}{\longrightarrow}} n \underset{\text { Glucose }}{\mathrm{C}_6 \mathrm{H}_{12} \mathrm{O}_6}$

On completing the reaction, excess $\mathrm{H}_2 \mathrm{SO}_4$ is neutralised by addition of chalk powder and solution is decolourised by activated charcoal.

The process which converts glucose into ethyl alcohol with the liberation of CO$_2$ is known as alcoholic fermentation. Such reactions are carried out by yeasts as a part of their anerobic respiration process. The process occurs in the presence of zymase enzyme, which is present in yeast. This method is used in the preparation of alcohol.

$\underset{\text { Glucose }}{\mathrm{C}_6 \mathrm{H}_{12} \mathrm{O}_6}+ \mathrm{Zymase }\rightarrow \underset{\text { Ethanol }}{2 \mathrm{C}_2 \mathrm{H}_5 \mathrm{OH}}+\underset{\begin{array}{c}\text { Carbon } \\ \text { dioxide }\end{array}}{2 \mathrm{CO}_2}$

Maltase converts maltose into glucose by hydrolysis as follows

Maltose $\mathrel{\mathop{\kern0pt\longrightarrow} \limits_{Maltase}^{Hydrolysis}} $ glucose + glucose

Xerophthalmia is a medical condition in which eye fails to produce tears. It may be caused by deficiency of vitamin (A). Hence, option (d) is the correct answer.

(ii) Anomeric crystalline form

(i) do not give Schiff's test, because, - CHO group is not free.

(iv) Pentaacetate do not react with$ \text { hydroxylamine, because } $

is not available.

So, statements (i), (ii) and (iv) support the cyclic structure of glucose.

$ \text { Zwitter ionic form of aspartic acid is } $

As, the species bear negatively charge over $\mathrm{COO}^{\ominus}$ and positivity charge over $\mathrm{H}_3 \stackrel{\oplus}{\mathrm{~N}}$-; due to migration of H -atom from -COOH to $-\mathrm{NH}_2$.

Hence, option (b) is the correct answer.

$ \text { (i) Histidine } $

$ \text { (ii) Valine } $

$ \text { (iii) Arginine } $

$ \text { (iv) Proline } $

Statement (a) is incorrect. Because $\alpha$-D-fructose and $\beta$-D-fructose are anomers, diastereomers and geometrical isomers and not enantiomers.

Rest of the given statements are correct.