Which chamber of the heart receives oxygenated blood from the lungs?

Answer 1

The left atrium receives oxygen-rich blood from the lungs through the pulmonary veins. After gas exchange occurs in the lungs—where carbon dioxide is released and oxygen is absorbed—the oxygenated blood travels through four pulmonary veins (two from each lung) and enters the left atrium. From there,

Answer 2

The previous expert answered the question very well. Just to add some points:

The heart has four chambers: two atria (top of the heart and smaller chambers), and two ventricles (bottom of the heart and larger chambers) and are split between right and left. Withing those chamber runs two tracks that are responsible for either put blood into the LUNGS or EVERYWHERE ELSE.

The heart is a closed circuit and by that, I mean that it's a big loop and nothing is lost from it. within the circuit you have two different paths that are serving two different purposes. The right side of the heart receives all the blood from the Vena Cava (Superior and Inferior) which carries all of the deoxygenated blood from the body. Once the blood enters the right side of the heart, it is in the right atrium from there it passes into the right ventricle, through the tricuspid valve, during Diastole (filling of the heart). Then it is sent from the right ventricle to the pulmonary trunk, through the pulmonary valve, during systole (emptying of the heart). The blood is carried through the pulmonary arteries into the pulmonary capillaries where the diffusion of gases facilitates the loss of CO2 and gaining of O2. The blood at this point is now Oxygenated and returns to the left atrium via the pulmonary veins. The blood travels from the left atrium to the left ventricle, through the Mitral (Bicuspid) valve, during diastole. Then the blood is sent to the Aorta from the left ventricle, through the Aortic valve, during systole. The blood from the aorta is carried to the rest of the body to deliver oxygen to your tissues.