1

### AIPMT 2003

Chargaff's rule states that in an organism
A
amount of adenine (A) is equal to that of thymine (T) and the amount of guanine (G) is equal to that of cytosine (C)
B
amount of adenine (A) is equal to that of guanine (G) and the amount of thymine (T) is equal to that of cytosine (C)
C
amount of adenine (A) is equal to that of cytosine (C) and the amount of thymine (T) is equal to that of guanine (G)
D
amounts of all bases are equal.

## Explanation

Amount of A = T and amount of G = C, this is stated by Chargaff’s rule.
2

### AIPMT 2003

Vitamin B12 contains
A
Fe (II)
B
Co (III)
C
Zn (II)
D
Ca (II)

## Explanation

Vit B12 also called Cyanocobaltamin, is anti-pernicious anaemia vitamin.
3

### AIPMT 2003

Glycolysis is
A
oxidation of glucose to glutamate
B
conversion of pyruvate to citrate
C
oxidation of glucose to pyruvate
D
conversion of glucose to haem.

## Explanation

Glycolysis is the oxidation of glucose. It is an anaerobic process and involves the degradation of glucose into two molecules of pyruvate with the generation of two molecules of ATP.
4

### AIPMT 2002

Which is not true statement?
A
$\alpha$-carbon of $\alpha$-amino acid is asymmetric.
B
All proteins are found in $L$-form
C
Human body can synthesise all proteins they need.
D
At pH = 7 both amino and carboxylic groups exist in ionised form.

## Explanation

Some proteins are also found in the D-form.