Divisions of the Nervous System Flashcards
What is the nervous system?
A control system to help us respond to the environment. It is a specialised network of cells in the human body and is our primary internal communication system. It uses fast, electrical signals to send messages.
Two main functions of the nervous system
1 - to collect, process and respond to information in the environment
2 - to co-ordinate the working of different organs and cells in the body
Central Nervous System
Responsible for complex processing of information and coordinating activities of the body. CNS receives sensory information from PNS, processes it and sends instructions back to the body for a response
Brain
Organ of nervous tissue where all conscious and most unconscious processing occurs
Spinal cord
Receives and transmits information between the brain and rest of the body. Also controls simple, automatic responses called reflexes
Peripheral nervous system
Body wide network of messenger neurons that deliver instructions to the body from CNS. Sensory (Afferent) neurons to CNS and motor (Efferent) neurons away from CNS
Somatic nervous system
A voluntary system under conscious control that controls skeletal muscles eg for movement
Autonomic nervous system
An involuntary system not under conscious control that controls actions of internal organs and glands eg breathing
Sympathetic nervous system
Increases bodily activities. Releases noradrenaline, activated in stress response (flight or fight) eg increased heart rate and increased sweat
Para - sympathetic nervous system
Decreases bodily activities. Releases acetylcholine, activates in rest (rest and digest) to relax body after stress eg decreased heart rate and decreased sweat
