Why is alternative splicing of pre-mRNA extremely crucial in humans?  BecauseGroup of answer choicesit generates proteins diversityexpands the versatility of genomic sequences through combinatorial controlit ensures that the introns are not transcribedA and BAll of the above

Alternative splicing of pre-mRNA is extremely crucial in humans for several reasons. Here are the step-by-step explanations:

1. It generates protein diversity: Alternative splicing allows different combinations of exons within a gene to be included or excluded during mRNA processing. This leads to the production of multiple mRNA isoforms, which can then be translated into different protein variants. This process greatly increases the diversity of proteins that can be produced from a limited number of genes.

2. It expands the versatility of genomic sequences through combinatorial control: By selectively including or excluding exons, alternative splicing can create different mRNA isoforms with distinct functional properties. This combinatorial control allows for the generation of proteins with different functions, subcellular localizations, or regulatory activities. It provides a way to expand the functional repertoire of the genome without the need for additional genes.

3. It ensures that the introns are not transcribed: In addition to generating protein diversity, alternative splicing also plays a role in removing introns from the pre-mRNA. Introns are non-coding regions of DNA that are transcribed into the pre-mRNA but do not code for proteins. Through alternative splicing, introns can be spliced out, ensuring that only the coding regions (exons) are retained in the mature mRNA.

Therefore, the correct answer is "All of the above" because alternative splicing of pre-mRNA in humans serves all of these important functions.