Biomolecules

Both (A) and (R) are true but (R) is not correct explanation for (A), as the amino acids exist in dipolar form due to presence of positive $\left(-\stackrel{+}{\mathrm{N}} \mathrm{H}_3\right)$ group and negative ( $-\mathrm{COO}^{-}$) group. The dipolar form is called as Zwitter ion form.

Fructose possess molecular formula $\mathrm{C}_6 \mathrm{H}_{12} \mathrm{O}_6$. Structure of $D$ and $L$ fructose are

$D$ and $L$ configurations are relative configurations. Glucose and fructose

both have -OH group on the bottom carbon to the right side. They have same $D$-configuration. Hence, they are called $D$-glucose and $D$-fructose. So, assertion (A) is true. Glucose rotates plane polarised light to the right side or clockwise direction. So, it is dextrorotatory.

Whereas fructose rotates plane polarised light to left side or anti-clockwise. So, fructose is laevorotatory. So, given reason (R) is false.

1 mole of sucrose on acid hydrolysis produces 1 mole of glucose and 1 mole of fructose.

$ \underset{\text { Sucrose }}{\mathrm{C}_{12} \mathrm{H}_{22} \mathrm{O}_{11}} \xrightarrow{\text { Acid hydrolysis }} \underset{\text { Glucose }}{\mathrm{C}_6 \mathrm{H}_{12} \mathrm{O}_6}+\underset{\text { Fructose }}{\mathrm{C}_6 \mathrm{H}_{12} \mathrm{O}_6} $

Molecular mass of sucrose

$ \begin{aligned} & =(12 \times \text { atomic mass of } \mathrm{C})+(22 \times \text { mass of } \\ & \mathrm{H})+(11 \times \text { Atomic mass of } \mathrm{O}) \\ & =(12 \times 12)+(22 \times 1)+(11 \times 16)=342 \mathrm{~g} \end{aligned} $

Therefore, amount of sucrose needed to produce 1 mole of glucose using acid hydrolysis is 342 g .

The structure of proteins is destroyed by the application of heat or chemical agents and the process i. called denaturation. It involves the disruption of both the secondary and tertiary structures of a protein, but the primary structure, which involves a sequence of amino acids does not get disturbed and remains intact. This results in the loss of the biological activity of the proteins.

The protein in milk is normally suspended in a colloidal solution, which means that the small protein molecules float around freely and independently. On adding lime juice to milk the pH decreases and the small protein molecules gets coagulated and forms large chain. This is denaturing of protein and causes curdling.

Therefore the (A) is false but (R) is true.

$\text { Sucrose } \xrightarrow{\text { Invertase }} \text { Glucose }+ \text { Fructose }$

$\begin{aligned} & \text { Proteins } \xrightarrow{\text { Pepsin }} \text { Peptides } \\ & \text { Starch } \xrightarrow{\text { Diastase }} \text { Maltose } \end{aligned}$

$\text { The correct match is A-II, B-III, C-IV. }$

Carbohydrates are stored in plants and animals in different forms because their storage needs and structures vary. In plants, carbohydrates are typically stored as starch, while in animals, they are stored as glycogen.

To understand this better, let's look at each storage form:

Starch: Starch is a polysaccharide that serves as a storage form of energy in plants. It is composed of two molecules, amylose and amylopectin, which are both polymers of glucose. Starch is stored in plastids (like chloroplasts and amyloplasts) within plant cells.

Glycogen: Glycogen is a highly branched polysaccharide formed of glucose units, similar to starch but more extensively branched. It is the primary storage form of carbohydrate in animals and is predominantly stored in the liver and muscle tissues.

Given these details, the correct forms of carbohydrate storage in plants and animals are:

Option D: Starch in plants and Glycogen in animals.

Glycylalanine is a dipeptide made up of glycine and L-alanine residues. When glycine and alanine link together, a water molecule is released and glycylalanine is formed which works as a metabolite:

Our body needs vitamin $\mathrm{B}_{12}$ to make red blood cells. Deficiency of vitamin $\mathrm{B}_{12}$ causes a rare blood disorder also known as pernicious anemia. It is characterised by inability of body to produce red blood cells.

Vitamin C is a water soluble vitamin. So, it is excreted with the urine. Other vitamins like, A, E and K are fat soluble thus, can be stored in the body.

But vitamin C cannot be stored in the body.

Glucagon is a peptide hormone produced by alpha cells of pancreas. It raises the concentration of blood glucose in human.

A peptide bond is formed when carboxyl group of $\alpha$-amino acid reacts with amine group of $\alpha$-amino acids. This proceeds by dehydration i.e. removal of a water molecule.

Fibrous proteins are characterized by their elongated, insoluble structure and often serve structural or mechanical roles. Among the options provided, keratin, collagen, and myosin are examples of fibrous proteins.

Albumin, on the other hand, is a globular protein that is soluble in water. It has a more spherical shape compared to the elongated shape of fibrous proteins. Albumin is found in blood plasma and has various functions including maintaining osmotic pressure.

So, the correct answer is:

Option B: Albumin.

Given structure of compound A is thymine, so its complementary base will be adenine.

Adenine form hydrogen bonds with thymine and cytosine will form hydrogen bond with guanine.

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 :