Identify different regions in the structure of myofibril
1.Z disc 2.A Band 3.M line 4.H zone 5.I band
Each sarcomere is limited by 2 Z discs.
The thick filaments produce the dark A band.
The thin filaments extend in each direction from the Z disk. Where they do not overlap the thick filaments, they create the light I band.
The H zone is that portion of the A band where the thick and thin filaments do not overlap.
The M line runs through the exact center of the sarcomere.