MUSCLE
SKELETAL MUSCLE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Thick filaments are made of a protein called actin.
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True
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False
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Either A or B
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None of the above
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Explanation:
Detailed explanation-1: -"Thick filaments are composed of actin.” This statement is false. Thin filaments (not thick) are made of actin protein subunits. Thick filaments are made of myosin proteins.
Detailed explanation-2: -The myofilaments are of two types: thick filaments composed of the protein myosin, and thin filaments composed mainly of the protein actin but with a complex of two other proteins, troponin and tropomyosin, closely associated with it.
Detailed explanation-3: -Thin filaments are comprised of two actin strands, each harboring equally separated troponin complexes, which bind Ca2+ to move tropomyosin cables away from the myosin binding sites and, thus, activate systolic contraction.
There is 1 question to complete.