Final answer:
The abbreviation PNS stands for Peripheral Nervous System, which connects the central nervous system to the rest of the body and is responsible for relaying information between the brain, spinal cord, and peripheral areas.
Step-by-step explanation:
The abbreviation PNS stands for Peripheral Nervous System. The Peripheral Nervous System is a major division of the overall nervous system, which includes all the nervous tissue outside the central nervous system (CNS). Its primary function is to connect the CNS to the limbs and organs, essentially acting as a communication relay between the brain and spinal cord, and the rest of the body. It incorporates a multitude of nerves that extend throughout the body, such as the sciatic nerve—which is the longest nerve in the human body—allowing for the transmission of sensory and motor signals to and from the CNS.
An example of the PNS at work is when it controls the digestive system through the parasympathetic nervous system, one of its two main subdivisions. Additionally, a bundle of axons within the PNS is known as a nerve. The Peripheral Nervous System plays a crucial role, comparable to a series of wires connecting the power plant (CNS) to various houses (the rest of the body) allowing for communication and control.