Z disk


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Related to Z disk: H zone, M line, Sliding filament mechanism

Z disk

See Z line.

Z disk

A thin, dark disk that transversely bisects the I band (isotropic band) of a striated muscle fiber. The thin filaments, made primarily of actin, are attached to the Z disk; the area between the two Z disks is a sarcomere, the unit of contraction.
See also: disk