The role of the transverse tube in skeletal muscle cells is []
A. Reservoir of calcium ions
B. Channels of calcium ions into and out of muscle fibers
Channels of nutrients into and out of muscle cells
D. Passing excitement deep into muscle cells
E. Combining calcium and troponin
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The enzyme that eliminates acetylcholine in the transmission of neuromuscular junction is []
A. Phosphodiesterase
B. Adenylate cyclase
C. ATPase
D. Cholinesterase
E. Carbonic anhydrase
The structural basis of direct electrical synaptic transmission between adjacent cells is []
A. Gap connection
B. Tight connection
C. Synapse connection
D. End plate connection
E. Connector connection
During tonic contraction, the action potential of muscle cells []
A. Increase the amplitude
B. Decrease the amplitude
C. the amplitude sometimes big and sometimes small
Decrease the frequency
E. No overlap
O2 and CO2 enter and exit the cell membrane in the body through []
A. Simple diffusion
B. Facilitated diffusion
C. Active transport
D. endocytosis
E. exocytosis
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