Why is the innervation ratio in the ocular muscles one motor axon per 23 muscle fibers, whereas in the gastrocnemius muscle, it is one motor axon per 1,000 muscle fibers?
A. The ocular muscles require finer control than moving the legs.
B. The innervation ratio has to do with the overall size of the muscle-the bigger the muscle, the fewer the muscle fibers per motor axon.
C. The gastrocnemius muscle contracts much harder than the ocular muscles do.
D. There are fewer muscle fibers in the gastrocnemius muscle than in the ocular muscles.
E. There are more nerves in the upper body than in the lower extremities.
Answer: A
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