How many weak hydrogen bonds are present between $A$ (Adenine) and $T$ (Thymine)?

What are the structures called that give an appearance as 'beads-on-string' in the chromosomes when viewed under an electron microscope?

Which $N_2$ base is absent in the structure of $RNA$?

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 $\%$)

The three-dimensional structure of the $t-RNA$ molecule is . . . . . . .

$A$ distinct mechanism that usually involves a short segment of $DNA$ with remarkable capacity to move from one location in a chromosome to another is called