Answer:Transcriptional Regulation
Explanation:
Eukaryotic gene expression can be regulated during the time of transcription and RNA processing, which takes place in the nucleus of the cell and then during the time of protein translation in the cytoplasm.
Further regulation is being carried during the time of post transnational modification. The conservation of energy is very important because it saves the overall energy and space in the body.
Hence, the most important point for the regulation would be transcriptional regulation.
<span>Estrogen is involved in a feedback mechanism associated with the follicular phase of menstruation. </span>
If it has valves then it is a vein.
The answer for this should be D
