MUSCLE
SKELETAL MUSCLE
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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I band
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A band
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Z disc
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H zone
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Detailed explanation-1: -The darker bands are called anisotropic bands (A bands). Together the I-bands and A-bands contribute to the striated appearance of skeletal muscle. Isotropic bands indicate the behavior of polarized light as it passes through I bands.
Detailed explanation-2: -The dark A band consists of parallel myosin thick filaments, in a hexagonal arrangement in cross-section. The thick filaments of a single sarcomere are connected to each other by means of the M disc at their centres.
Detailed explanation-3: -Hint: The muscle fibres contain parallelly arranged myofibrils which have alternate light and dark bands. The dark present on the myofibril is called ‘A-band’ or anisotropic band and the light band present on the myofibril is called I-band or isotropic band.