1.5

Question 1

explain the cardiac cycle

Answer 1

For blood to flow from the atria into the ventricles, the tricuspid and bicuspid valves must open, while the SL valves are closed.
Blood being pumped out of the heart is forced from the ventricles and out through the arteries
The semi-lunar valves are open and the tricuspid and bicuspid valves are closed to stop blood flowing backwards