Final answer:
Reflex arcs are components of the nervous system facilitating rapid responses, consisting of sensory receptors, neurons, and effectors. Somatic reflex arcs involve skeletal muscles, while autonomic reflex arcs control involuntary functions through the sympathetic and parasympathetic systems.
Step-by-step explanation:
Reflex arcs are fundamental components of the nervous system that enable rapid responses to stimuli without the direct involvement of the brain. Reflex arcs consist of sensory receptors, an afferent sensory neuron that carries the impulse to the spinal cord, an integrating center (usually the spinal cord or brain stem), an efferent motor neuron that carries the impulse away from the integrating center, and the effector, which is usually a muscle or gland that reacts to the initial stimulus.
Somatic reflex arcs control the body's voluntary movements and involve skeletal muscles. Autonomic reflex arcs, which are part of the autonomic nervous system, control involuntary functions such as the regulation of blood pressure or digestive processes.
The autonomic nervous system is further divided into the sympathetic and parasympathetic systems, each mediating different types of reflexes based on the body's needs for rest or activity.
Short and long reflexes differ in their pathways: short reflexes are mediated by local circuits within the gastrointestinal tract, whereas long reflexes involve sensory neurons sending signals to the central nervous system, which in turn sends out motor commands to the effectors.