Nucleotides are linked by

If a double stranded $DNA$ has $20$ per cent of cytosine, calculate the per cent of adenine in the $DNA$.

The chemical nature of chromosome is as follows

If the sequence of one strand of $DNA$ is $5^{\prime}$ $A T G C A T C G 3'$ , find the sequence of complementary strand in $5^{\prime} \rightarrow 3^{'}$ direction

If the distance between two consecutive base pairs is $0.34\, nm$ and the total number of base pairs of a $DNA$ double helix in a typical mammalian cell is $6.6 \times 10^{9}$ $bp,$ then the length of the $DNA$ is approximately 

Assertion : In a $DNA$ molecule, $A-T$ rich parts melt before $G-C$ rich parts.

Reason : In between $A$ and $T$ there are three $H-$ bond, whereas in between $G$ and $C$ there are two $H-$ bonds.