The Circulatory System
Beginning of paper
in anatomy and physiology is the course taken by
the blood through the arteries, capillaries, and veins and back to the heart. In
humans and the higher vertebrates, the heart is made up of four chambers the
right and left auricles, or atria, and the right and left ventricles. The right
side of the ....
Middle of paper
.... the blood to the lungs. Blood is prevented from returning into the
auricle by the tricuspid valve, which completely closes during contraction of
the ventricle. In its passage through the lungs, the blood is oxygenated, that
is, then it is brought back to the heart by the four pulmonary veins, which
enter the left auricle. When this chamber contracts, blood is forced into the
left ventricle and then by ventricular contraction into the aorta. The bicuspid,
or mitral, valve prevents ....
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Page count: 6 (approximately 250 words per page)
