Final answer:
The Peripheral Nervous System (PNS) consists of the somatic nervous system and the autonomic nervous system (ANS). The somatic system controls voluntary movements while the ANS regulates involuntary functions. The ANS operates through neurotransmitters like acetylcholine and norepinephrine, acting on specific receptors.
Step-by-step explanation:
The Peripheral Nervous System (PNS) includes sensory and motor neurons that connect the central nervous system (CNS) to the rest of the body. The PNS is divided into the somatic nervous system, which handles voluntary control of body movements through control of skeletal muscles, and the autonomic nervous system (ANS), which regulates involuntary body functions such as heartbeat and digestion. The ANS is further divided into the sympathetic and parasympathetic divisions, each with its own neurotransmitters and receptors.
In the somatic nervous system, the neurotransmitter acetylcholine activates muscles. The ANS uses several neurotransmitters, including acetylcholine and norepinephrine, which work on different sets of receptors. The sympathetic division predominantly uses norepinephrine (noradrenaline) on adrenergic receptors to stimulate 'fight or flight' responses, while the parasympathetic division mainly uses acetylcholine on muscarinic receptors to promote 'rest and digest' responses.