Answer:
The labelled structure of the heart is attached below. The valves in the heart prevent the backward flow of blood. These valves are actual flaps that are located on each end of the two ventricles (lower chambers of the heart). They act as one-way inlets of blood on one side of a ventricle and one-way outlets of blood on the other side of a ventricle.
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xoxo,
cafeology
