CBSE
Which one of these elements is found in vitamin B12 ?
Fe
Zn
Mg
Co
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
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 - D-glucose and - D-glucose, is :
+ 19°
+ 112°
+ 52°
+ 100°
The structural formula of an amino acid, isoleucine is :
CH3--COOH
(CH3)2-CH--COOH
--COOH
(C2H5)2-CH--COOH
Which of the following reaction is catalysed by enzyme maltase ?
starch maltose
maltose glucose
lactose maltose
maltose glucose + fructose
Enzymes with two sites are called :
apoenzyme
allosteric enzyme
holoenzyme
conjugate enzyme
Subunits present in haemoglobin are
2
3
4
5