List three ways by which eukaryotes process mrna after transcription.

The post transcription modification include three ways i.e., capping, polyadenylation and splicing.

1. 5' Capping- mRNA capping is catalyzed by capping enzyme which is associated with RNA polymerase II. This enzyme adds the guanosin residue to 5' end of mRNA then methyl transferase adds methyl group to N⁷ position this guanine. Capping protects mRNA from degradation by enzymes presents in the cell.

2. Polyadenylation: In polyadenylation many adenosine residue is added at 3'end of mRNA by poly(A) polymerase. This poly A tail helps in exporting mRNA out of nucleus and binding of translational factors.

3. Splicing: In splicing process the non coding introns are removed from RNA so that only coding region i.e., exons are left in mRNA. It is important to remove unwanted sequence like introns which hinders in protein formation.

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.

compost can be added to topsoil as a:

pesticide