What does atrial contraction do just before ventricular contraction?
It closes the semilunar valves to prevent backflow.
It empties the venae cavae into the atria.
It tops up the ventricles with blood.
It pumps blood into the arteries under high pressure.
Flashcards for Edexcel A A Level Biology Cardiac control, ECGs and exercise physiology, covering the key terms, definitions and processes you need to recall for Paper 1, Paper 2 and Paper 3. 23 cards, matched to the Edexcel A A Level Biology (9BN0) specification.
