Perimysjärjestysten

Perimysjärjestysten, also known as the Peripheral Nervous System (PNS) in English, is the part of the nervous system that connects the central nervous system (brain and spinal cord) to the rest of the body. It is responsible for transmitting information between the central nervous system and the limbs and organs. The PNS is divided into two main divisions: the somatic nervous system and the autonomic nervous system.

The somatic nervous system is further divided into the sensory division, which transmits sensory information to the central nervous system, and the motor division, which transmits motor commands from the central nervous system to the muscles. The autonomic nervous system, on the other hand, is responsible for regulating involuntary functions such as heart rate, digestion, and respiration. It is divided into the sympathetic and parasympathetic divisions, which often work in opposition to each other to maintain homeostasis.

The PNS consists of 12 cranial nerves, which emerge from the brain, and 31 pairs of spinal nerves, which emerge from the spinal cord. These nerves contain both sensory and motor neurons, which transmit information between the central nervous system and the peripheral tissues. The PNS is involved in various physiological processes, including sensation, movement, and the regulation of internal organs. Damage to the PNS can result in a variety of neurological symptoms and disorders, highlighting its importance in maintaining overall health and function.