What prevents the backflow of blood inside the heart during contraction?
(a) thick muscular walls of ventricles
(b) valves
(c) thin walls of atria
(d) all of the above

Question

What prevents the backflow of blood inside the heart during contraction?
(a)	thick muscular walls of ventricles
(b)	valves
(c)	thin walls of atria
(d)	all of the above

MyClass24 · Accepted Answer

valves

What prevents the backflow of blood inside the heart during contraction? (a) thick muscular walls of ventricles (b) valves (c) thin walls of atria (d) all of the above