Final answer:
The human nervous system is split into the central nervous system (CNS), with the brain and spinal cord, and the peripheral nervous system (PNS), which includes somatic and autonomic systems influencing voluntary and involuntary functions.
Step-by-step explanation:
The human nervous system is divided into two major subdivisions: the central nervous system (CNS) and the peripheral nervous system (PNS). The CNS comprises the brain and spinal cord, which are responsible for processing and transmitting information throughout the body. The PNS extends from the CNS and is further divided into the somatic and autonomic systems. The somatic system controls voluntary muscular movements and the reception of external stimuli, while the autonomic system governs involuntary functions such as heart rate, digestion, and respiratory rate, and is further divided into sympathetic and parasympathetic systems, which respectively prepare the body for 'fight or flight' responses or 'rest and digest' functions.