How does a plasma membrane maintain homeostasis?

Which best explains why there are 64 possible codons in the genetic code and only 20 amino acids that make protiens of living organisms on earth

2. given that most biochemical (other than coal) rocks react with hydrochloric acid, what does that tell you about organisms?

Scientists discover two populations of mice on either side of a major river. the two populations have almost identical genes but the mice from one side cannot breed with mice from the other. this is most likely because