試題詳解

43. Which of these statements about muscle contraction is FALSE?
(A) Ca²⁺ is required for all muscle contraction.
(B) Troponin is present in skeletal muscles and smooth muscles.
(C) When a skeletal muscle shortens during contraction, the H band and sarcomere shorten.
(D) Skeletal muscles but not cardiac muscles require neural stimulation to contract.
(E) The sarcoplasmic reticulum and transverse tubules are well-developed in skeletal muscles and poorly developed in smooth muscles.