The figure illustrates an important concept in the genetic implication of $DNA$. Fill in the blanks $A, B$,and $C$.

Genes that maintain their position on a chromosome are called....

Write a comparative note on the properties of $DNA$ and $RNA$.

Match the following and select the correct option:
Column $A$ | Column $B$
$(i)$ Oncogenes | $(1)$ Causes $AIDS$
(ii) Single circular $DNA$ | $(2)$ $Lac$-Operon concept
(iii) Splicing | $(3)$ Component of bacterial chromosome
(iv) Jacob and Monod | $(4)$ Processing of $mRNA$ molecules
| $(5)$ When activated cause cancer
Select the correct sequence for $(i), (ii), (iii), (iv)$ respectively.

Base substitution caused by base analogs is known as:

Consider the following four statements $(a-d)$ and select the option which includes all the correct ones only $:-$
$(a)$ Transcription and translation can be coupled in bacteria.
$(b)$ The split gene arrangements represent the advanced feature of the genome.
$(c)$ The process of splicing represents the dominance of $\text{RNA-}$world.
$(d)$ The presence of introns in split gene is reminiscent of antiquity.