A private in the U. S. Army is stationed at Ft. Bragg, North Carolina. He has been admitted to the infirmary with complaints of a severe headache and high fever. Upon questioning, he revealed that he had received a tick bite several days earlier. Two days after admission, he starts to develop a rash, beginning on his hands and feet and spreading towards his torso. What should be considered first in the diagnosis?

Check all that occur during ventricular systole. a. the av valves open to allow blood to enter the ventricles from the atria. b. the av valves open to allow blood to enter the ventricles from the atria. c. the semilunar valves remain closed throughout systole to prevent backflow of blood into the ventricles. d. the semilunar valves remain closed throughout systole to prevent backflow of blood into the ventricles. e. the semilunar valves open to allow blood to flow into the large arteries. f. the semilunar valves open to allow blood to flow into the large arteries. g. the av valves close to prevent backflow of blood into the atria.