Fast-twitch fibers contract up to _________ times more rapidly than slow-twitch fibers.
A)3
B)8
C)10
D)12

Question

Fast-twitch fibers contract up to _________ times more rapidly than slow-twitch fibers.​ 
A)3 
B)8 
C)10 
D)12

Quizplus · Accepted Answer

Fast-twitch fibers contract up to 10 times more rapidly than slow-twitch fibers. This is due to the differences in the way they generate energy and transmit signals. Fast-twitch fibers rely on anaerobic metabolism and have a higher concentration of enzymes and myosin ATPase, which enable rapid contractions. Slow-twitch fibers, on the other hand, rely on aerobic metabolism and have a higher concentration of mitochondria and capillaries, which allow them to sustain contractions for longer periods of time.

Fast-Twitch Fibers Contract Up to _________ Times More Rapidly Than