Question

What class of skeletal muscle fibers is found in small motor units?

a) Type I (slow-twitch) fibers
b) Type IIa (fast-twitch oxidative) fibers
c) Type IIb (fast-twitch glycolytic) fibers
d) Type III intermediate fibers

Answer 1

The class of skeletal muscle fibers found in small motor units is Type I (slow-twitch) fibers.

Step-by-step explanation:

The class of skeletal muscle fibers found in small motor units is Type I (slow-twitch) fibers.

Fibers can be classified into three main types based on their contraction speed and ATP production. Slow oxidative (SO) fibers contract slowly and use aerobic respiration to produce ATP, while fast oxidative (FO) fibers have fast contractions but can switch to anaerobic respiration. Fast glycolytic (FG) fibers have fast contractions and primarily use anaerobic glycolysis.

In small motor units, the muscles require precise and controlled movements, which are better achieved with slow-twitch (Type I) fibers.