Question

Consider the following statements and select the option which include all the correct ones only :-
(a) Transcription and translation can be coupled in bacteria
(b) The split gene arrangements represents the advanced feature of the genome
(c) The process of splicing represents the dominance of RNA-world
(d) The presence of introns in split gene is reminiscent of antiquity
(1) a, b, d
(2) a, b, c
(3) a, c, d
(4) b, c, d

Answer 1

(3) a,c,d.

b statement is wrong

Answer 2

The option that includes all the correct statements only is (3) a, c, d.

• Transcription and translation are coupled in bacteria because there is no division of compartments in a prokaryotic cell. Thus, both the processes take place in the same compartment.
• The split gene arrangement indicates that the first genetic material was RNA and not DNA. It thus represents an ancient feature of the genome.
• The process of splicing represents the RNA world i.e. the protein-making machinery evolved around RNA and not DNA.
• The presence of introns (non-coding region) in split gene arrangement is reminiscent of antiquity.