Question

Which of these occurs during the atrial systole?

• A. Both atria contract simultaneously
• B. Action potential is generated by the AVN initially
• C. Tricuspid valve closes
• D. The semilunar valves remain open

Answer 1

Answer:

A. Both atria contract simultaneously

• During the atrial systole, both the atria contract simultaneously while the ventricles remain relaxed.

• It occurs due to the action potential generated by the SAN.

• The tricuspid and bicuspid valves open.