This is an example of Homeostasis or Adaptation.
Blood vessels in the ear dilate or constrict to help regulate body temperature.
Answer: It helps the cell absorb as many different molecules as possible.
Explanation: the cell membrane, provides protection for a cell. It also provides a fixed environment inside the cell, and that membrane has several different functions. One is to transport nutrients into the cell and also to transport toxic substances out of the cell.
Answer:
I believe through 'Natural Selection'. This occurs through the following steps
1) Genetic Variation
2) Over-Production
3) Struggle for existence
4) Survival of the fittest
5) Advantageous characteristics passed on to offspring
Hope this answered your question.