Are there any structures within the heart or vessels that prevent the backflow of blood? if so, what are they and where are they located?

Are there any structures within the heart or vessels that prevent the backflow of blood? If so, what are they and where are they located?

Explanation:  

The heart is made up of four cavities. These are the following: Two ventricles and Two atria.

The left ventricle is the one that exerts the greatest muscular strength, because from here the blood is pumped to the systemic circulation. To prevent blood from flowing backward between two beats, there are several types of heart valves: one type between the atria and the ventricles, and another between the ventricles and arteries.

The semilunar valves in turn prevent blood from returning from the pulmonary artery and the aorta to the ventricles, when after pumping they dilate again for muscle relaxation.

The answer is: Yes, and they are semilunar valves.

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between the two muscle layers is the myenteric or auerbach's plexus, which controls peristalsis. in the colon, the muscularis externa is much thicker because the feces are large and heavy, requiring more force to push along. the stomach has a third layer of muscularis externa: the inner oblique layer.