In a given $DNA$ segment the number of nucleotides of guanine is $75$ and those of thymine is $75$. The total number of nucleotides in the segment will be
$75$
$750$
$225$
$300$
One turn of $DNA$ possesses
Genes are chemically
$DNA$ is double helix and
Which of the following is correct for Watson and Crick's model of $DNA$. It is duplex with
Genetically active area of chromosome is called