Myofibril Terminology

Question 1

The structural unit of a myofibril, consists of thick and thin filaments

Answer 1

sarcomere

Question 2

made up of Globular-actin which link up to make filamentous actin, which form a double helix structure to make and actin strand. There are myosin binding site located on the actin. Troponin and Tropomyosin are found on this filament

Answer 2

thin filament

Question 3

made up of two twisted heavy chains with globular ends that make up the cross-bridge. The cross bridge has actin sites and ATPase binding sites. There are four light chains located on globular ends.

Answer 3

Thick filament

Question 4

Can see as dark band. Thick and thin filaments intersect. Extends from to the end of each thick filament (per sarcomere)

Answer 4

A-band

Question 5

Can see as lighter color band. Thick filaments do not intersect here. Goes from z-band

Answer 5

I-band