Which of the following nitrogenous bases is not found in $DNA$?

Which scientists proposed the complete and systematic model of $DNA$?

In $DNA$,the two polynucleotide chains are . . . . . . .

If the sequence of one strand of $DNA$ is $5^{\prime}-ATGCATCG-3^{\prime}$,find the sequence of the complementary strand in the $5^{\prime} \rightarrow 3^{\prime}$ direction.

What is the number of base pairs $(bp)$ in a nucleosome (in $,bp$)?

Deoxyadenosine,deoxyguanosine,deoxycytidine,and deoxythymidine are $....................$.