Vertebrate striated muscles composed of twitch fibers are able to produce a graded contraction by
A) Recruiting different numbers of motor units.
B) Summing EPSPs in the motor end-plate region.
C) Having excitatory and inhibitory input to a single muscle.
D) Vertebrate muscles are unable to produce graded contractions.
Answer: A
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What results from right ventricular failure?
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