Which statement about stimulants and depressants is correct. a. stimulants speed up the way the brain works, and depressants slow it down. b. stimulants slow the activity of the brain, and depressants speed it up

The purity of ecstasy is always in question, why? (short answer)

Which statement best illustrates that problem solving can create new medical devices? robert hooke was in charge of verifying the information that was sent to the royal academy. william harvey did experiments with apes to learn about the circulatory system. the stethoscope was invented because the physician did not want to put his head on women's chests to listen to their heart and lungs. anton van leeuwenhoek was a very curious man and looked at just about everything under this microscope.

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.