MEDICAL PHYSIOLOGY

Detailed explanation-1: -The two atrioventricular valves, the tricuspid and mitral valves, are both open, so blood flows unimpeded from the atria and into the ventricles. Approximately 70–80 percent of ventricular filling occurs by this method.

Detailed explanation-2: -Atrial contraction (First Phase) This active filling of ventricles becomes valuable during physical activity. When pressure in the atrium increases, blood rush into the ventricles through the opened mitral valve.

Detailed explanation-3: -Atrial contraction (atrial systole) then ejects blood from the atrium and into the ventricle, which is still in diastole, and this completes ventricular filling.

Detailed explanation-4: -Diastole begins with the closing of the aortic valve (or pulmonic) and ends with the closing of the mitral valve (or tricuspid). This period encompasses the ventricular relaxation and filling. Diastole represents when the blood vessels return blood to the heart in preparation for the next ventricular contraction.

Detailed explanation-5: -Ventricular systole: lasts about 0.3 seconds-both ventricles contract, blood is forced to the lungs via the pulmonary trunk, and the rest of the body via the aorta.