The Role of Tropomyosin in Skeletal Muscle is ________

Question

The role of tropomyosin in skeletal muscle is ________.
A) the contracting unit
B) containing neurotransmitters
C) blocking the active sites on the actin to regulate muscle contraction
D) blocking the active sites on myosin to regulate muscle contraction

Accepted Answer

Tropomyosin is a protein that wraps around the actin filaments in a muscle fiber, covering the active sites that myosin heads use to attach and pull the filaments past each other during muscle contraction. When calcium ions bind to troponin, it changes shape and moves the tropomyosin out of the way, exposing the active sites and allowing muscle contraction to occur. Therefore, tropomyosin plays a crucial role in regulating muscle contraction by blocking the active sites on actin.