What is the main structural difference between the somatic and autonomic nervous systems?

The number of neurons needed to transmit signals

Explanation:

Somatic Nervous System: it regulates the voluntary movement of skeletal muscles, its major components are cranial and spinal nerves Autonomic Nervous System: its involuntarily managed, its major components are the sympathetic and parasympathetic nervous systems and it acts on glans and smooth and cardiac muscles.

Their main structural difference between both systems is that the somatic nervous system needs only one efferent neuron to transmit a signal while on the other hand, the autonomic nervous system needs two efferent neurons and ganglia to transmit a signal.

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