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Isometric contraction cannot be altered by increasing number of sarcomere in series?


plz explain ur answer and
what if question says " in parallel"
 

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Simply because increasing the number of sarcomeres in series will affect the (length) of the muscle fiber which has nothing to do with the mechanism of generating the isometric contraction which is characterized by increase in muscle tone with no shortening nor lengthening of the muscle. On the other hand, the higher the sarcomeres in parallel means the greater thickness (mass) of the muscle and consequently the greater tone that can be generated by that particular muscle. For that reason when the heart has to pump against increased resistance it does so by increasing the thickness of its chambers; although there will be no increase in the no. of sarcomeres; to be able to generate a greater isovolumetric contraction to pump the blood.
 
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