nervous system Flashcards
what is the nervous system?
a specialised network of cells in the human body
our primary internal communication system
communicates using electrical and chemical signals
main functions:
- collect, process and respond to environmental info
- co-ordinate working of diff organs and cells
subsystems:
- central nervous system
- peripheral nervous system
what is the CNS?
made up of brain and spinal cord
origin of all complex commands and decisions
brain- centre of all conscious awareness
highly developed in humans- distinguishes our higher mental functions from other animals
deivided into 2 hemispheres
spinal cord- extension of brain
passes messages to and from brain
connects nerves to PNS
reflex actions (e.g. pulling hand away from stove)
what is the PNS?
transmits messages via millions of neurons to CNS from outside world and from CNS to muscles and glands in body
subsystems:
- autonomic nervous sytem (ANS)
- somatic nervous system (SNS)
what is the ANS?
transmits info to and from internal bodily organs
operates automatically
governs vital body functions e.g. breathing, heart rate, digestion, etc.
divisions- sympathetic and parasympathetic nervous systems
what is the SNS?
transmits info from receptor cells in sense organs to CNS
receives info from CNS directing muscles to act
what is the SNS?
transmits info from receptor cells in sense organs to CNS
receives info from CNS directing muscles to act
