Which of the following is an example of post-transcriptional control of gene expression? a. gene amplification contributing to cancerb. the removal of introns and alternative splicing of exonsc. the addition of methyl groups to cytosine bases of dnad. the binding of transcription factors to a promotere. the folding of dna to form heterochromatin

The correct answer is: b. the removal of introns and alternative splicing of exons

Post-transcriptional regulation includes processes of regulation between transcription and translation such as RNA splicing, capping, addition of poly-A tail,  RNA editing.

RNA splicing represents the process of RNA processing in which newly synthesized pre-mRNA transcript is converted into a mature mRNA. This process occurs only in eukaryotic organism and includes the removal of introns and joining together the exons. RNA splicing might occur during or immediately after transcription and it is performed by spliceosome (complex of small nuclear ribonucleo proteins).

Alternative splicing is a regulated process in which a single gene can code for multiple proteins because particular exons of a gene may be included within or excluded from the final mRNA.

correct answer is option a.

tropopause, stratopause and mesopause have all in common aspect that is point of maximum temperature in its layer of the atmosphere. all layers of atmosphere observe abrupt change in temperature. tropopause is the boundary between troposphere and stratosphere. stratopause is the boundary between stratosphere and mesosphere. mesopause is the boundary between mesosphere and thermosphere. these all boundaries are ranges between altitude of 0 to 80 km.

digestion

it excretes wastes