ANATOMY

Detailed explanation-1: -Type 2 B: Fast glycolytic (FG) fibers have fast contractions and primarily use anaerobic glycolysis. The FG fibers fatigue more quickly than the others.

Detailed explanation-2: -Human fast-twitch muscle fibers generate high power in a short amount of time but are easily fatigued, whereas slow-twitch fibers are more fatigue resistant.

Detailed explanation-3: -Type IIB fibers have high myosin ATPase activity (pH 9.4), are fast twitch, have low oxidative and high glycolytic capacity, and fatigue rapidly.

Detailed explanation-4: -In humans, type I, or slow-twitch, fibers possess slower twitch speeds and are relatively fatigue resistant. Type IIa fibers, or fast oxidative glycolytic (FOG) fibers, present higher twitch speeds than type I fibers but are less fatigue resistant.

Detailed explanation-5: -Fast glycolytic fibers fatigue quickly, permitting them to only be used for short periods. However, during these short periods, the fibers are able to produce rapid, forceful contractions associated with quick, powerful movements. These different fiber types can be easily identified in poultry.