blood enters the left atrium from the lungs vessel.
blood enters the left atrium from which vessel?
lungs
the left and right sides of the heart are named from a dorsal view, i.e., looking at the heart from the back or from the perspective of the person whose heart it is. there are four chambers in a heart: an atrium (upper) and a ventricle (lower) on both the left and right sides. in mammals and birds, blood from the body goes to the right side of the heart first. blood enters the upper right atrium, is pumped down to the right ventricle and from there to the lungs via the pulmonary artery. blood going to the lungs is called the pulmonary circulation. when the blood returns to the heart from the lungs via the pulmonary vein, it goes to the left side of the heart, entering the upper left atrium. blood is then pumped to the lower left ventricle and from there out of the heart to the body via the aorta. this is called the systemic circulation. a cardiac shunt is when blood follows a pattern that deviates from the systemic circulation, i.e., from the body to the right atrium, down to the right ventricle, to the lungs, from the lungs to the left atrium, down to the left ventricle and then out of the heart back to the systemic circulation.
cardiac shunt
in an anatomically correct heart the right atrium and right ventricle are working together to supply blood to the pulmonary artery, similarly to how the left atrium and the left ventricle work simultaneously to supply blood to the aorta. during the process of the heart contracting and releasing the right atrium and left atrium contract at the same time, while the left ventricle and right ventricle relax. in opposition, when the left atrium and right atrium are relaxed the left ventricle and right ventricle contract pushing blood to either the aorta or pulmonary artery. in an anatomically correct heart the atria are smaller than the ventricles. the ventricles include more muscle in order to push high quantities of blood throughout the body. normal blood flow throughout the heart begins at the superior vena cava coming from the upper half of the body and the inferior vena cava coming from the lower half of the body. next blood will be in the right atrium and will flow uninterrupted through the tricuspid valve through to the right ventricle. the blood from the right ventricle should go to the pulmonary artery via the pulmonary valve.the blood from the pulmonary vein enters the left atrium, then flows through the mitral valve to the left ventricle. after the left ventricle is filled with blood the aortic valve opens allowing blood to go through, which the blood then enters the aorta and goes to the rest of the body.
crisscross heart