Answer:
The circulatory system, also known as the cardiovascular system, is a simple loop which starts, and ends, with your heart. It is a closed system, meaning blood does not enter or leave the system during its journey from your heart to your body and back again.
Explanation:
Answer:
A new mutation
Explanation:
A mutation refers to the random changes in the DNA of organisms. A mutation changes the allele and genotype frequencies by the introduction of a new allele in the gene pool.
However, mutations are not the major factor responsible for changes in the gene pool of a population as mutations are rare. The rate of mutations is very slow and does not allow it to serve as a major factor to change the allele and genotype frequencies.
I believe the awnser is B