$A$ gene is made up of

The bond between the phosphate group and the hydroxyl group of sugar is........

The histone that links nucleosomes together is called ......

In his experiments on the chemistry of $DNA$,Chargaff estimated the base composition of human sperms and found that Adenine constituted $31\%$ and Guanine $19\%$. The quantity of Cytosine in the $DNA$ of human somatic cell is likely to be (in $\%$)

$A$ $DNA$ fragment contains $12$ nucleotides. What is the ratio of purine and pyrimidine nitrogenous bases in it?

How many base pairs of $DNA$ are wrapped around a histone octamer?