The Nervous System Flashcards
What is the nervous system
Primary internal communication system
Billions of neurons
What is the central nervous system comprised of
Brain and spinal cord
The role of the brain
Ensure life is maintained - breathing or heartbeat (eg brain stem)
Other areas involved in planning, problem solving (eg pre frontal cortex)
The role of the spinal cord
Carries messages using neurons to and from the brain and peripheral nervous system
Relays information from the brain to the rest of the body
Allows the brain to monitor bodily processes like breathing and digestion
Arc reflex
Involuntary and rapid response to a stimulus
Minimise any damage to body from potentially harmful conditions
Essential for survival
No involvement of conscious parts of the brain
What is the peripheral nervous system comprised of
Somatic and autonomic
What is the role of the peripheral nervous system
Relay nerve impulses from the CNS to the rest of the body and from the body back to the CNS
From 12 pairs of cranial nerves, 31 pairs of spinal nerves , and lots of sensory and motor pathways allows the CNS to be aware of what’s going on in the body and in the outside world
Somatic nervous system
CC- motor and somatosensory cortex
Made up of 12 pairs of cranial nerves and 31 pairs of spinal nerves
Connects CNS to senses
Contains sensory and motor neurons
Sensory (afferent) and motor (efferent) components
The autonomic nervous system
CC- top of brain stem , hypothalamus and pituitary gland
Responsible for homeostasis
Many functions are automatic - require little or no conscious thought
Comprised of sympathetic and parasympathetic branches
Differences between autonomic and somatic NS
-autonomic nervous system is unconscious whereas the somatic nervous system is under conscious control
-the somatic nervous system has both sensory and motor neurons whereas the. Autonomic nervous system uses only motor neurons
-the control system for the autonomic nervous system is located in the motor and somatosensory cortex, whereas the control centre for the autonomic nervous system is located in the brain stem
Sympathetic branch
Prepares body for rapid action when exposed to threat
Carries out biological changes to prepare the body for activity
Activates fight or flight
Parasympathetic branch
Store and conserve resources once emergency has passed
Returns body to normal balanced state
Rest and digest
