The sarcomere and the sliding filament model of contraction
During contraction myosin ratchets along actin myofilaments compressing the I and H bands. During stretching this tension is release and the I and H bands expand. The A-band remains constant throughout as the length of the myosin myofilaments does not change.
This diagram describes the sliding filament model of contraction. Terms include A-band, I-band, H-band, CapZ, titin, Z-line, myocin head, myocin tail, actin filament, relaxed, contracted, and M-line.
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"Sarcomere.png."
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