NEET BIOLOGY

Detailed explanation-1: -When all four chambers of the heart are relaxed, it is considered to be in a condition of joint diastole. During this procedure, deoxygenated blood from the superior and inner vena cava is sent to the right auricle, while oxygenated blood is delivered to the left auricle through the pulmonary vein from the lungs.

Detailed explanation-2: -During joint diastole, tricuspid and bicuspid valves are open. It is at this point the blood from the pulmonary veins and vena cava flows in to the left ventricle and right ventricle through the atria. So, left atrium receives oxygenated blood through pulmonary veins.

Detailed explanation-3: -During joint diastole, when both the auricles and the ventricles relax simultaneously the atria receive blood from the great veins and the coronary sinus. Since blood is received by the auricles from the veins it is deoxygenated blood. So, the correct option is ‘deoxygenated blood’.

Detailed explanation-4: -Joint diastole is the process in which blood from great veins and coronary flow into the atria. In this process the cardiac cycle is finished within 0.8 seconds.

Detailed explanation-5: -Blood reaches the corresponding auricles via veins during the joint diastole stage. Due to this blood filling, atrioventricular valves (Bicuspid and Tricuspid valves) open during joint diastole and allow blood to flow from the atria to the ventricles and semilunar valves are closed.