Biomolecules — Page 4 | JEE Chemistry

Q31

Among the following, the essential amino acid is :

A Alanine

B Valine

C Aspartic acid

D Serine

Correct Answer

Option B

Solution

Valine is considered as an essential amino acid since the human body is not capable of synthesising it.

Alanine, aspartic acid and serine can be synthesised by all living organisms, plants and animals.

Therefore, they are known as non-essential amino acids.

Q32

Among the following, the incorrect statement is :

A Maltose and lactose has 1, 4 - glycosidic linkage.

B Sucrose and amylose has 1, 2 - glycosidic linkage

C Cellulose and amylose has 1, 4 - glycosidic linkage.

D Lactose contains

\beta

-D-galactose and

\beta

-D-glucose.

Correct Answer

Option B

Solution

(a) Both maltose and lactose have 1,4-glycosidic linkage. (b) In sucrose, C1- $\alpha$ of glucose is connected to C2- $\beta$ of fructose.

In amylose, C1 of one glucose unit is attached to C4 of other glucose through $\alpha$ -glycosidic linkage. (c) Cellulose has 1,4- $\beta$ -D-glycosidic linkage, but amylose has 1,4- $\alpha$ -D-glycosidic linkage. (d) In lactose, C1- $\beta$ of galactose is linked to C4- $\beta$ of glucose.

Q33

Glucose and Galactose are having identical configuration in all the positions except position

A C–5

B C–3

C C–2

D C–4

Correct Answer

Option D

Solution

Glucose and galactose differs in configuration on C4.

Q34

Amylopectin is compound of :

A

\alpha

-D-glucose, C1 – C4 and C1 – C6 linkages

B

\beta

-D-glucose, C1 – C4 and C2 – C6 linkages

C

\beta

-D-glucose, C1 – C4 and C1 – C6 linkages

D

\alpha

-D-glucose, C1 – C4 and C2 – C6 linkages

Correct Answer

Option A

Solution

Amylopectin is a component of starch and starch is a polymer of $\alpha$ -D-glucose.

Amylopectin has $\alpha$ -1, 6-glycosidic linkage in addition to $\alpha$ -1,4-glycosidic linkage and is a cross-linked polymer.

Q35

The peptide that gives positive ceric ammonium nitrate and carbylamine tests is :

A Ser-Lys

B Asp-Gln

C Gln-Asp

D Lys-Asp

Correct Answer

Option A

Solution

Positive Ceric ammonium nitrate test is given by alcohol (- OH).

Positive Carbylamine test is given by 1o amine (-NH2).

Among those peptide you can see only in (A) Serine(Ser)Lysine(Lys) has alcohol (- OH) and 1o amine (-NH2).

Q36

Maltose on treatment with dilute HCI gives :

A D-Galactose

B D-Glucose and D-Fructose

C D-Glucose

D D-Fructose

Correct Answer

Option C

Solution

Maltose on treatment with dil.

HCl gives D-glucose.

Hydrolysis of maltose yields two moles of $\alpha$ - D-glucose.

Thus, it is composed of two $\alpha$ -D-glucose units in which C-1 of one glucose unit (I) is linked to C-4 of another glucose unit (II).

The free aldehyde group can be produced at C-1 of second glucose in solution and it shows reducing properties.

So, it is a reducing sugar.

Q37

Out of the following, which type of interaction is reponsible for the stabilisation of

\alpha

-helix structure of proteins ?

A Covalent bonding

B vander Waals forces

C Ionic bonding

D Hydrogen bonding

Correct Answer

Option D

Solution

$\alpha$ -helix structure of proteins is stabilised by H-bonds between hydrogen of —NH and oxygen of - C = O group is amino acids.

Q38

Match and .

List - I		List - II
(a)	Valium	(i)	Antifertility drug
(b)	Morphine	(ii)	Pernicious anaemia
(c)	Norethindrone	(iii)	Analgesic
(d)	Vitamin ${B_{12}}$	(iv)	Tranquilizer

A (a)-(i), (b)-(iii), (c)-(iv), (d)-(ii)

B (a)-(iv), (b)-(iii), (c)-(ii), (d)-(i)

C (a)-(ii), (b)-(iv), (c)-(iii), (d)-(i)

D (a)-(iv), (b)-(iii), (c)-(i), (d)-(ii)

Correct Answer

Option D

Solution

(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.

Q39

Which of the glycosidic linkage between galactose and glucose is present in lactose?

A C-1 of galactose and C-6 of glucose

B C-1 of glucose and C-6 of galactose

C C-1 of galactose and C-4 of glucose

D C-1 of glucose and C-4 of galactose

Correct Answer

Option C

Solution

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.

Q40

Match with .

List - I		List - II
(a)	Sucrose	(i)	$\beta$ -D-Galactose and $\beta$ -D-Glucose
(b)	Lactose	(ii)	$\alpha$ -D-Glucose and $\beta$ -D-Fructose
(c)	Maltose	(iii)	$\alpha$ -D-Glucose and $\alpha$ -D-Glucose

A (a)

\to

(iii), (b)

\to

(ii), (c)

\to

(i)

B (a)

\to

(i), (b)

\to

(iii), (c)

\to

(ii)

C (a)

\to

(ii), (b)

\to

(i), (c)

\to

(iii)

D (a)

\to

(iii), (b)

\to

(i), (c)

\to

(ii)

Correct Answer

Option C

Solution

Sucrose

\to \alpha

-D- Glucose and $\beta$ -D- Fructose Lactose

\to \beta

-D- Galactose and $\beta$ -D- Glucose Maltose

\to \alpha

-D- Glucose and $\alpha$ -D- Glucose