The genetic material in the bacterium $Escherichia$ $coli$ $(E. coli)$ is:

Read the following statements and choose the set of correct statements:
$(a)$ Euchromatin is loosely packed chromatin
$(b)$ Heterochromatin is transcriptionally active
$(c)$ Histone octamer is wrapped by negatively charged $DNA$ in nucleosome
$(d)$ Histones are rich in lysine and arginine
$(e)$ $A$ typical nucleosome contains $400 \ bp$ of $DNA$ helix
Choose the correct answer from the options given below:

Genetic information is carried by long-chain molecules made up of

In the structure of $DNA$,a purine base of one nucleotide is linked to a pyrimidine base of the opposite nucleotide by which type of bond?

In a $340 \text{ Å}$ long $DNA$ strand, how many nitrogen base pairs are present?

The nitrogenous bases of the two strands of $DNA$ are joined by