PHYSIOLOGY
CARDIOVASCULAR PHYSIOLOGY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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contract
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relax
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extend
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pull the vanes of the valves towards the atria
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Detailed explanation-1: -The papillary muscles are “nipple” like projections of the myocardia and contract when the myocardia contracts. As a result, they pull on the chordae tendinae and help to prevent prolapsing of the AV valves. The chordae tendinae and the papillary muscles occur in both the left and right ventricles.
Detailed explanation-2: -During the relaxation phase of the cardiac cycle, the papillary muscles are also relaxed and the tension on the chordae tendineae is slight (image b above). However, as the myocardium of the ventricle contracts, so do the papillary muscles.
Detailed explanation-3: -The papillary muscles which are located on the ventricles of the heart are attached to the cups of the atrioventricular valves through the chordae tenndineae and this will contract for preventing prolapsing or inversion of these valves on ventricular contraction which is their function.