Which of the following is a function of the protein called ubiquitin?
a.) it attaches to proteins that are marked for destruction in the cell.
b.) it assists in the removal of introns from a eukaryotic pre-mrna.
c.) it initiates the formation of a transcription complex.
d.) it adds the 3' and 5' caps to eukaryotic pre-mrna.

The correct answer is: a) It attaches to proteins that are marked for destruction in the cell.

Ubiquitin is a regulatory protein of eukaryotic cell with the various of function. The mechanism of its action involves the addition of ubiquitin to a substrate protein (ubiquitination). Ubiquitin regulatory roles are:

•marking thee proteins for degradation via the proteasome,  

•alter the cellular location of proteins,  

•promoting or preventing protein interactions.

good thing- during decomposition the organic molecules in organic matter are broken down into simpler organic molecules that require further decomposition or into mineralised nutrients

bad thing- it can be harmful in crop productivity

the answer will be a) proteins i believe