The countercurrent heat exchanger that prevents arterial blood from overheating the testes is the pampiniform plexus of veins. The pampiniform plexus helps to regulate testicular temperature, allowing sperm maturation. It surrounds the testicular arteries and works as a countercurrent heat-exchanger system to cool the arterial blood before entering the testes. This is because the sperms can not develop if the testis is at body temperature.
A cladogram is a branching diagram that shows the cladistic relationship between a number species. It comes from the greek clados meaning branch and gramma meaning character. It is not to be confused with an evolutionary tree since it does not show the relationship between ancestors and descendants plus it also lacks the ability to show how they have changed over time. The major components of a cladogram are the tip (the start of the lineage), root (the end of the lineage) and node (where two or more lineages combine).
The short plants<span> are </span>not able<span> to </span>compete<span> with </span>tall plants<span> for </span>sunlight<span>. ... The </span>tall plants, however, aremore susceptible<span> to </span>wind damage<span>. Which </span>type<span> of </span>selection<span> are the </span>plants experiencing? directionalselection<span> ... They are believed to have come from </span>one<span> common ancestor and just become </span>more<span> and</span>more<span> different due to .</span>
B
Explanation
Sodium Fluoride
