Nervous System

• The nervous system is a complex network of nerves and cells that carry messages to and from the brain and spinal cord to various parts of the body
• The nervous system is considered as the body's storage center of information and also the body's control system
• The nervous system is responsible for controlling and coordinating all the organ systems by sending messages from the brain through nerve signals
• Central Nervous System (CNS) serves as the main processing center of the nervous system and consists of the brain and spinal cord
• The brain, part of the CNS, has three main parts: Cerebrum, Cerebellum, and Brain stem
• The spinal cord, part of the CNS, serves as a channel for signals between the brain and the majority of the body parts, controlling some simple musculoskeletal reflexes even without the processing of the brain
• Peripheral Nervous System (PNS) connects the central nervous system to the organs and limbs
• The PNS has two main divisions: Somatic Nervous System for voluntary control of body movements and Autonomic Nervous System for involuntary control of body movements
• The Autonomic Nervous System has two subdivisions: Sympathetic Nervous System activated in stress and Parasympathetic Nervous System maintaining body functions and restoring the body to a normal or relaxed mode
• The nerve cell, also called a neuron, is the basic unit of the nervous system and has a cell body containing the nucleus, dendrites, and axons
• Dendrites carry impulses toward the cell body while axons carry impulses away from the cell body, with synapse being the gap between neurons
• The nervous system and endocrine system work together to maintain the body's homeostasis, which is the state reached when each part of the body functions in equilibrium with other parts
• Feedback mechanisms are used by most body systems to maintain homeostasis, regulating bodily functions such as body temperature, amount of water, metabolic wastes, and blood calcium level