MCQ
In a contracted skeletal muscle fibre
  • $M-$ line disappears
  • B
    $H-$zone elongates
  • C
    $I-$band remains constant
  • D
    $A-$band disappears

Answer

Correct option: A.
$M-$ line disappears
a
In a contracted muscle fibre, following happens -
$H-$zone shortens
$I-$band shortens
$A-$band remains constant.

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