Question

Type I: slow, oxidative, red

Type IIA: fast, oxidative, red
Type IIB: fast, glycolytic, white

The muscle cells listed above will most likely fatigue in what order, from first to last?
First-------------------------------------------Last
A. Type I TypeIIA TypeIIB
B. Type I TypeIIB TypeIIA
C. TypeIIA TypeI TypeIIB
D. TypeIIB TypeIIA TypeI
E. All three types will fatigue at the same rate.

Answer 1

Muscle cells fatigue in the order of Type IIB (fast, glycolytic, white) first, Type IIA (fast, oxidative, red) second, and Type I (slow, oxidative, red) last, which corresponds to choice D of the given options.

Step-by-step explanation:

The order in which muscle cells are likely to fatigue from first to last is based on their metabolic properties and contracting capabilities. The Type IIB muscle fibers, being fast glycolytic fibers, use anaerobic metabolism, which leads them to fatigue the quickest.

The Type IIA muscle fibers have fast contractions and utilize aerobic metabolism but can switch to anaerobic respiration, causing them to fatigue more quickly than Type I but less quickly than Type IIB. Finally, the Type I muscle fibers are slow oxidative and are the most resistant to fatigue as they use aerobic metabolism to produce energy.

Therefore, the sequence of fatigue from first to last would be: Type IIB, then Type IIA, and lastly Type I. This corresponds to choice (D) TypeIIB TypeIIA TypeI.