1. When this is released by the synaptic vesicles, it causes a change in the muscle fiber membrane potential that spreads along the T tubules. a - Acetylcholine (ACh)  d - a, b, and c c - ATP b - calcium

1. Describe the sequence of events which lead to skeletal muscle contraction. Start with depolarization at the neuromuscular junction (NMJ).

During muscle contraction, binding sites for myosin are uncovered by the movement of A. Tropomysin B. Actin myofilaments C. ADP D. Troponin

10. Which of the following skeletal muscle fiber structure is not part of the “triad”? a. sarcomere b. t-tubule c. terminal cisternae of the SR d. b and c e. a, b, and c

44.

17. Which of the following properties of the structure of skeletal muscle is not true?   A. Comprised of individual cells.   B. Have well defined striations.   C. Have T-tubules.   D. Communicate electrically through gap junction channels (connexins).   E. Have well defined sarcomeric structure and extensive sarcoplasmic reticulum.

What causes relaxation in a skeletal muscle fiber Select one: a. Myosin remains attached to actin b. Calcium is pumped away from myofibrils c. Voltage gated potassium channels open d. Voltage gated sodium channels inactivate

The structure (a specialized synapse) that allows neurons to control our skeletal muscle fibers is called the: 19. A. sarcolemma extracellular inard B. neuromuscular junction C. sarcoplasmic reticulum D. cross-bridge axiom arcople acell

1. When cross-bridge binding occurs, actin and myosin shorten and the muscle contracts. True False

Which event occurs earlier in time, as compared to the others listed, to bring about skeletal muscle cell contraction? Ca++ release from sarcoplasmic reticulum     Ca++ binding to troponin complex on actin     tropomyosin shifting off the actin filament     activation of ryanodine receptors in S.R.     T-tubule action potential