How does the cardiovascular system oxygenate blood by returning it to the lungs?

Answer 1

breathing in, expands the chest which in turn lowers the pressure in the thoracic cavity. The lower pressure causes air to fill the lungs, the same lower pressure cause the pressure in the right atria to be lower, allowing for more blood to flow in, increasing the venous input thus increasing the cardiac output of the heart.

Answer 2

simply put, the cardiovascular systems sole purpose is to deliver oxygen to the organs. lets start with the left ventricle (largest part of the heart) pushing oxygenated blood to organs, 1st dibs on the best blood goes to the heart itself, then the aorta (largest artery) branches off and 2nd in line is the brain via the dual carotid arteries. the aorta then curves down and gives blood to organs and muscles and skin where capillary beds are. by the time the blood gets to the capillary beds its depleted of oxygen and returns to the lungs via the veins. veins return deoxygenated blood to the right atrium of the heart, the R. atrium pumps it to the R ventricle and it pumps the deox blood to the lungs. when the deox blood gets to the lungs it releases carbon dioxide it has picked up on the way to delivering oxygen. The hemoglobin in blood releases the CO2 and then grabs the oxygen. The left atrium then pulls the oxygenated blood from the lungs and dumps it into the L ventricle to be pumped to the body again. easier to see is this...

L ventricle--->arteries---->capillary beds----> veins----> R atria -----> R ventricle ----> lungs ----> L atria

Answer 3

The heart does that. The vein does not.

The heart is the strongest muscle in your body. It pumps ALL the blood in the circulatory system. The veins are the path to bring blood back to the heart.