Which of the Following is Both a Protein and a Structural

Question

Which of the following is both a protein and a structural component of thin filaments?
A) actin
B) myosin
C) myofibrils
D) T-tubules

Accepted Answer

Actin is a protein that makes up the majority of thin filaments in muscle cells. It plays a critical role in muscle contraction by interacting with myosin to produce the sliding effect of muscle contraction. Myosin is also a protein involved in muscle contraction, but it is a component of thick filaments rather than thin filaments. Myofibrils are the contractile units of muscle cells that contain the thin and thick filaments. T-tubules are invaginations of the plasma membrane that allow for the propagation of action potentials in muscle cells.