I believe that the loop of Henle is the hairpin structure that connects the proximal and distal convoluted tubules. The loop of Henle is composed of the ascending and the descending limb. The descending loop of Henle connects the proximal convoluted tube with the ascending limb of the loop of Henle, while the ascending loop of Henle connects the descending limb of the loop of Henle with the distal convoluted tubule.
Natural selection act directly upon <u>Alleles</u>
Explanation:
Genes, such as that of fur color, have many variants called alleles. Natural selection act on the alleles and chooses the best fit for an environment and eliminates the disadvantageous ones from the population over generations. Mutations are a rare occurrence that increases the number of allelic variants of a genes on which natural selection can act upon.
the intercourse of a human or animal to make babies
The term for this is Hourly Wage. This can be then used for calculating gross annual salary.
I think it is
<span>D. It takes place along an unraveled section of DNA</span>