First, the yellow fever virus is phagocytosed by white blood cells. The phagocytosed white blood cell then travel through the lymph vessel. Since lymph node contain white blood and filter lymph, the yellow fever phagocytosed with white blood cell establish in the lymph node.
During exercise there is an increase in physical activity and muscle cells respire more than they do when the body is at rest. The heart rate increases during exercise. The rate and depth of breathing increases - this makes sure that more oxygen is absorbed into the blood, and more carbon dioxide is removed from it.
Answer:
The answer would be A, to lead sperm cells to the ovary. Hope this helps you out!
