Biomolecules — Page 5 | JEE Chemistry

Q41

Which among the following pairs of Vitamins is stored in our body relatively for longer duration?

A Thiamine and Vitamin A

B Ascorbic acid and Vitamin D

C Thiamine and Ascorbic acid

D Vitamin A and Vitamin D

Correct Answer

Option D

Solution

Vitamins which are soluble in fat and oils but insoluble in water are fat-soluble vitamins, which are stored in our body relatively for a longer time. e.g.

Vitamin A and Vitamin D Thiamine (Vit B1) and Ascorbic acid (Vit C) are water-soluble.

Q42

The secondary structure of protein is stabilised by:

A Hydrogen bonding

B glycosidic bond

C Peptide bond

D van der Waals forces

Correct Answer

Option A

Solution

The secondary structure of a protein is stabilised by hydrogen bonding.

Q43

{C_{12}}{H_{22}}{O_{11}} + {H_2}O\overset{{Enzyme\,A}}\longrightarrow \mathop {{C_6}{H_{12}}{O_6}}\limits_{Glu\cos e} + \mathop {{C_6}{H_{12}}{O_6}}\limits_{Fructose}

\mathop {{C_6}{H_{12}}{O_6}}\limits_{Glu\cos e} \overset{{Enzyme\,B}}\longrightarrow 2{C_2}{H_5}OH + 2C{O_2}

In the above reactions, the enzyme A and enzyme B respectively are :

A Zymase and Invertase

B Invertase and Amylase

C Amylase and Invertase

D Invertase and Zymase

Correct Answer

Option D

Solution

$\therefore$ Enzyme A is Invertase Enzyme B is Zymase

Q44

Fructose is an example of :

A Heptose

B Pyranose

C Ketohexose

D Aldohexose

Correct Answer

Option C

Solution

Fructose contains ketone group so it is ketose.

Q45

Thiamine and pyridoxine are also known respectively as :

A Vitamin B2 and Vitamin E

B Vitamin E and Vitamin B2

C Vitamin B6 and Vitamin B2

D Vitamin B1 and Vitamin B6

Correct Answer

Option D

Solution

Vitamine-B1 is also known as Thiamine while Vitamin B-6 is known as Pyridoxine.

Q46

Given below are two statements : one is labelled as Assertion (A) and other is labelled as Reason (R). Assertion (A) : Sucrose is a disaccharide and a non-reducing sugar. Reason (R) : Sucrose involves glycosidic linkage between C1 of

\beta

-glucose and C2 of

\alpha

-fructose. Choose the most appropriate answer from the options given below :

A Both (A) and (R) are true but (R) is not the true explanation of (A).

B (A) is false but (R) is true.

C (A) is true but (R) is false.

D Both (A) and (R) are true and (R) is the true explanation of (A)

Correct Answer

Option C

Solution

Sucrose is example of disaccharide & non reducing sugar Assertion : Correct Sucrose involves glycosidic linkage between C1 of $\alpha$ -D-glucose C2 of $\beta$ -D-fructose Reason : Incorrect

Q47

Sugar moiety in DNA and RNA molecules respectively are

A

\beta

-D-2-deoxyribose,

\beta

-D-deoxyribose.

B

\beta

-D-2-deoxyribose,

\beta

-D-ribose

C

\beta

-D-ribose,

\beta

-D-2-deoxyribose.

D

\beta

-D-deoxyribose,

\beta

-D-2-deoxyribose.

Correct Answer

Option B

Solution

DNA contains $\Rightarrow$ $\beta$ – D – 2 – deoxyribose RNA contains $\Rightarrow$ $\beta$ – D – ribose

Q48

The structure of protein that is unaffected by heating is

A secondary structure

B tertiary structure

C primary structure

D quaternary structure

Correct Answer

Option C

Solution

The primary structure of protein is unaffected by physical 'or' chemical changes.

Q49

Given below are two statements. Statement I : Maltose has two

\alpha

-D-glucose units linked at C1 and C4 and is a reducing sugar. Statement II : Maltose has two monosaccharides :

\alpha

-D-glucose and

\beta

-D-glucose linked at C1 and C6 and it is a non-reducing sugar. In the light of the above statements, choose the correct answer from the options given below :

A Both Statement I and Statement II are true.

B Both Statement I and Statement II are false.

C Statement I is true but Statement II is false.

D Statement I is false but Statement II is true.

Correct Answer

Option C

Solution

Maltose is composed of two $\alpha$ -D-glucose units in which $C_{1}$ of one glucose unit and $C_{4}$ of second glucose unit are linked.

Q50

A polysaccharide 'X' on boiling with dil H2SO4 at 393 K under 2-3 atm pressure yields 'Y'. 'Y' on treatment with bromine water gives gluconic acid. 'X' contains

\beta

-glycosidic linkages only. Compound 'X' is :

A starch

B cellulose

C amylose

D amylopectin

Correct Answer

Option B

Solution

Cellulose contains $\beta$ -glycosidic linkages only.

Structure of cellulose On boiling with dil. $\mathrm{H}_{2} \mathrm{SO}_{4}$ at $393 \mathrm{~K}$ under 2-3 atm, ' $X$ ' forms glucose, which given gluconic acid on treatment with bromine water.