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

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

Define the following terms: Bacteriophages and $DNA$.

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:

The base sequence for a nucleic acid segment is given as $CAG, AGG, CGA, CCA$. From this,it can definitely be concluded that it is a segment of:

The nucleosome core is made up of ............ .