Question

Which of the following is the most common type of alternative splicing in animals and involves making mRNA

molecules that lack a complete exon?
A) intron retention
B) mutually exclusive exons
C) cassette exons
D) alternative promoters
E) alternative splice site

Answer 1

The most common type of alternative splicing in animals is intron retention, where an mRNA molecule lacks a complete exon. This alternative splicing allows for the production of different protein products from a single gene.

Step-by-step explanation:

The most common type of alternative splicing in animals that involves making mRNA molecules lacking a complete exon is intron retention. In this type of splicing, an intron is retained within the mRNA, resulting in an mRNA molecule that lacks a complete exon. This alternative splicing mechanism allows for the production of different protein products from a single gene.

For example, let's consider a gene that has exons A, B, C, and D, with introns between them. Through intron retention, the mRNA molecule may retain the intron between exons B and C, resulting in an mRNA molecule that lacks exon C. This alternative splicing can lead to the production of different protein products with distinct functions.