A receiving chamber of the heart where the oxygenated blood arrives from the alveoli in the lungs.
The atrium situated on the left side of the heart.
The left upper chamber of the heart that receives oxygenated blood from the pulmonary veins.
This refers to the top-left chamber within the heart. During every heartbeat, the left atrium becomes filled with oxygenated blood, originating from the lungs through the pulmonary veins. Following this, the mitral valve opens, enabling the blood to be pushed into the left ventricle, from where it is subsequently pumped throughout the body.