Question

Which of the following involves the splicing out of introns?

a) Only DNA replication

b) Neither DNA replication nor transcription

c) Both DNA replication and transcription

d) Only transcription

Answer 1

b. Neither DNA replication nor transcription.

Intron splicing occurs after transcription, i.e, it is a post-transcriptional event.

DNA replication and transcription use DNA polymerase and RNA polymerase respectively. These polymerase enzymes add complementary nucleotides (dNTPs and rNTPs respectively) to the existing strand.

DNA replication involves the splicing of RNA fragments in the lagging strand and joining Okazaki fragments. However, these RNA sequences are not introns.

Intron splicing occurs after primary RNA is synthesized. Capping at the 5'-end, intron splicing, and polyadenylation at 3'-end are the three events that occur after or during transcription, which make mature mRNA.