In the context of the Introduction to the Peripheral Nervous System, what is the primary function of the peripheral nervous system (PNS)?

• A. To relay sensory information to the central nervous system (CNS) and carry motor commands from the CNS to muscles and glands
• B. To process and integrate information within the brain and spinal cord
• C. To produce cerebrospinal fluid and protect the brain from mechanical injury
• D. To secrete hormones into the bloodstream to regulate long-term body functions

Answer: (A)

Verified step by step guidance

1. Step 1: Understand the overall organization of the nervous system, which is divided into the central nervous system (CNS) and the peripheral nervous system (PNS). The CNS includes the brain and spinal cord, while the PNS consists of all the nerves outside the CNS.
2. Step 2: Recognize that the primary role of the PNS is to serve as a communication network that connects the CNS to the rest of the body, including muscles, glands, and sensory organs.
3. Step 3: Identify the two main functions of the PNS: first, to relay sensory information from sensory receptors throughout the body to the CNS; second, to carry motor commands from the CNS to muscles and glands to elicit responses.
4. Step 4: Differentiate the PNS functions from those of the CNS, which processes and integrates information, and from other systems like the cerebrospinal fluid production or endocrine system functions, which are not roles of the PNS.
5. Step 5: Conclude that the primary function of the PNS is to act as a communication pathway that transmits sensory input to the CNS and motor output from the CNS to effectors such as muscles and glands.