Which one of the following biomolecules is insoluble in water?

• α-keratin

• haemoglobin

• ribonuclease

• adenine

Correct configuration of the following is

• 1S, 2S

• 1S, 2R

• 1R, 2S

• 1R, 2R

583.

Which one of the following statements is true for protein synthesis (translation)?

• Amino acids are directly recognized by m-RNA.

• The third base of the codon is less specific.

• Only one codon codes for an amino acid.

• Every t-RNA molecule has more than oneamino acid attachment.

Assertion : Maltose is a reducing sugar which gives two moles of D-glucose on hydrolysis.

Reason : Maltose has a 1,4-β-glycosidic linkage.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false.

• If both assertion and reason are false.

The specific rotation of equilibrium mixture of $\mathrm{\alpha }$ - D-glucose and $\mathrm{\beta }$ - D-glucose, is :

• + 19°

• + 112°

• + 52°

• + 100°

The structural formula of an amino acid, isoleucine is :

• CH₃-$\stackrel{\underset{|}{{\mathrm{NH}}_2}}{\mathrm{CH}}$-COOH

• (CH₃)₂-CH-$\stackrel{\underset{|}{{\mathrm{NH}}_2}}{\mathrm{CH}}$-COOH

• $\stackrel{{\mathrm{CH}}_3}{\underset{{\mathrm{C}}_2{\mathrm{H}}_5}{\underset{|}{\stackrel{|}{\mathrm{CH}}}}}$-$\stackrel{\underset{|}{{\mathrm{NH}}_2}}{\mathrm{CH}}$-COOH

• (C₂H₅)₂-CH-$\stackrel{\underset{|}{{\mathrm{NH}}_2}}{\mathrm{CH}}$-COOH

Which of the following reaction is catalysed by enzyme maltase ?

• starch $\to$ maltose

• maltose $\to$ glucose

• lactose $\to$ maltose

• maltose $\to$ glucose + fructose

Enzymes with two sites are called :

• apoenzyme

• allosteric enzyme

• holoenzyme

• conjugate enzyme

Subunits present in haemoglobin are

• 2

• 3

• 4

• 5

Assertion : Carboxypeptidase is an exopeptidase.

Reason : It cleaves the N-terminal bond.

• If both assertion and reason are true and reason is the correct explanation of assertion

• If both assertion and reason are true but reason is not the correct explanation of assertion

• If assertion is true but reason is false

• If both assertion and reason are false.