SCIENCE
CIRCULATORY SYSTEM
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Relaxation phase of the cardiac muscle
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Contraction phase of the cardiac muscle
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Either A or B
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None of the above
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Detailed explanation-1: -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-2: -Diastole is the period of the cardiac cycle that encompasses ventricular relaxation, passive and active filling of blood into the heart, and the period just prior to ejection.
Detailed explanation-3: -Systole is the contraction phase of the cardiac cycle, and diastole is the relaxation phase.
Detailed explanation-4: -filling occurs during diastole, which has 4 phases: (1) isovolumic relaxation; (2) rapid filling phase; (3) slow filling, or diastasis; and (4) final filling during atrial systole (atrial kick.)
Detailed explanation-5: -Atrial and Ventricular diastole (chambers are relaxed and filling with blood) Atrial systole (atria contract and remaining blood is pushed into ventricles) Ventricular systole (ventricles contract and push blood out through aorta and pulmonary artery)