please answer my questions at the earliest i have bio exam on tuesday.

why light band is called isotrophic band?

why dark band is called anisotropic band?

what is fatigued?

what is sesamoid?

please reply at the earliest.thank you.

Light band is called isotropic  because it consists of thin filaments and is not interfered by thick filaments and hence bringing uniformity.

Dark band is called anisotropic because of the opposite reason as it is an area of both thick and thin filaments.

Fatigued is tiredness (physical or mental or both)

Sesamoid are bones that are connected only to tendons.