Although an Individual Person's Distribution of Skeletal Muscle Fiber Types

Multiple Choice

Although an individual person's distribution of skeletal muscle fiber types is primarily genetically determined, there exists some evidence that fiber types can change in response to exercise to a limited degree (ie. a slow glycolytic fiber can change to a fast oxidative fiber) . If such a change were to occur, which of the following proteins MUST change in some manner as the transition from one muscle type to another occurs?

A) actin
B) troponin
C) myosin
D) Ca²⁺-ATPase