Final answer:
Visceral reflex arcs differ from somatic reflex arcs because visceral arcs involve two motor neurons in a two-step pathway from the CNS to the effector, whereas somatic arcs involve a direct pathway from the CNS to skeletal muscles.
Step-by-step explanation:
Visceral reflex arcs differ from somatic reflex arcs in that visceral arcs involve two motor neurons. A somatic reflex arc directly connects sensory neurons from the central nervous system (CNS) to skeletal muscles, leading to muscle contraction. In contrast, the efferent branch of a visceral reflex involves a preganglionic fiber projecting from the CNS to a ganglion and then a postganglionic fiber that extends from the ganglion to the target effector, such as cardiac muscle, smooth muscle, or glandular tissue.
The autonomic nervous system, which includes visceral reflex arcs, can operate through long reflexes that involve the CNS or short reflexes that act peripherally without CNS involvement. The autonomic system targets include cardiac and smooth muscles, as well as glandular tissues, differentiating it from the somatic system's skeletal muscle targets.