Final answer:
The statement that T-tubules carry depolarization to the muscle fiber interior is true. They facilitate the spread of action potentials to the sarcoplasmic reticulum, causing calcium release and muscle contraction.
Step-by-step explanation:
The statement that T-tubules carry depolarization to the muscle fiber interior is True. T-tubules, or transverse tubules, are specialized structures within muscle cells that serve as pathways for action potentials to rapidly spread through the cell. Upon excitation, an action potential travels along the sarcolemma and into the T-tubules, reaching the sarcoplasmic reticulum (SR). This results in the opening of calcium channels in the SR membrane, allowing calcium ions (Ca++) to diffuse into the sarcoplasm. The increase in Ca++ concentration in the sarcoplasm triggers the contraction of the muscle fiber by activating the sarcomeres, which are the contractile units within the muscle.