(As seen in the discussion of spinal cord reflexes, although these muscles are called the voluntary muscles, they can move involuntarily when a reflex response occurs. When people are walking, raising their hands in class, smelling a flower, or directing their gaze toward the person they are talking to or to look at a pretty picture, they are using the somatic nervous system. The somatic nervous system is made up of the sensory pathway, which is all the nerves carrying messages from the senses to the central nervous system (those nerves containing afferent neurons), and the motor pathway, which is all the nerves carrying messages from the central nervous system to the voluntary, or skeletal, more info muscles of the body-muscles that allow people to move their bodies (those nerves composed of efferent neurons). One of the parts of a neuron is the soma, or cell body (remember that the word soma means “body”). The Peripheral Nervous System The Somatic Nervous System The PNS can be divided into two major systems: the somatic nervous system, which consists of nerves that control the voluntary muscles of the body, and the autonomic nervous system (ANS), which consists of nerves that control the involuntary muscles, organs, and glands. It is this system that allows the brain and spinal cord to communicate with the sensory systems and enables the brain and spinal cord to control the muscles and glands of the body. The peripheral nervous system or PNS (see Figure 2.7 and also refer back to Figure 2.5) is made up of all the nerves and neurons that are not contained in the brain and spinal cord. The term peripheral refers to things that are not in the center or that are on the edges of the center. Your computer does not support HTML5 audio
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