Nervous System Flashcards
what does cns do
sends and receives messages to and from the pns
what does the brain do
- processes sensory information
- coordinates a response to that information
what does the spinal cord do
- connects the brain to the pns
- receives sensory info from pns and sends to the brain
- receives motor information from the brain and sends it to various parts of the body using the pns
what is the pns and what does it do
pns is made up of the entire network of nerves outside the cns
- carries sensory information to the cns
- carries motor information to the cns
what is the somatic nervous system and what does it do
controls conscious and voluntary muscle movements
- initiates skeletal movement
- carries sensory information to the CNS (afferent)
- carries motor information from the cns (efferent)
what does the autonomic nervous system do
The autonomic nervous system controls involuntary bodily functions, such as regulating heart rate, blood pressure, and breathing
what does the sympathetic nervous system do
The sympathetic nervous system (SNS) prepares the body for physical activity and stress by activating the “fight,flight or freeze” response.
Increases:
- heart rate
- respritory rate
- blood pressure
- pupil dilation
what does the parasympathetic nervous system do
“Rest and Digest”
The parasympathetic nervous system relaxes and restores the body after periods of stress or danger.
- slows heart rate
- constricts pupils
- controls respiratory rate
what is a conscious response
a conscious response to a sensory stimulus is a reaction that involves awareness and is voluntary.
what is a unconscious response
an unconscious response to a sensory stimulus is a reaction that dosen’t involve awareness. it is involuntary and automatic.
what is a spinal reflex
a spinal reflex is an unconscious and involuntary response that occurs automatically without imput from the brain. this allows for a faster reaction time in potentially harmful situations.
steps to detect a spinal reflex stimulus
- sensory stimulus detected by sensory receptors
- sensory neurons carry information via sensory (afferent) pathway to spinal cord.
- interneurons in spinal cord initiate an involuntary motor movement
- this is relayed to motor neurons and carried via a motor (efferent) pathway to muscles
- muscles perform reflex response without input from the brain
steps in detecting and responding to sensory stimuli
- sensory stimulus detected by sensory receptors
- sensory neurons carry information via sensory (afferent) pathway to the cns
- the brain receives, processes and coordinates a response
- this is relayed to motor neurons and carried via a motor (efferent) pathway to muscles
- muscles initiate voluntary movement
