┊✯ ❥˙ 。..... NCERT Structure of myofibril :- >Each myofibril consist of alternate dark and light band. >Dark band - contain myosin protien and is called A-band or Anisotroic band. >Light band - Contain actin protien and is called I Band or Isotropic band. >I Band is bisected by an elastic fiber called ‘Z’ line. Actin filament (thin flament) are firmly attached to the ‘Z’ lines. >Myosin filament (thick filament) in the ‘A’ Band are also held together in the middle of ‘I’ Band by thin fibrous membrane called ‘M’ line. >The portion between two successive ‘Z’ lines is considered as functional unit of contraction and is called a sarcomere. ▃✧▃▃▃✧▃▃ ┊ ┊ ┊ ┊ ┊ ┊ ✿ ✿ 1.8K views08:50