B13.1 - Coordination and Response Flashcards
How do electrical impulses travel?
along neurones
What is in the central nervous system?
brain and spinal cord
what is in the perpheral nervous system?
NERVES outside of the brain and spinal cord
what is the role of the nervous system?
coordination and regulation of body functions
(control your body, give feedback about the world)
what is a reflex action?
automatically and rapidly integrating and coordinating stimuli with the responses of effectors
what are sense organs?
groups of receptor cells responding to specific stimuli
5 examples of stimuli
-light
-sound
-touch
-temperature
-chemicals
how do voluntary responses work?
1) stimulus –> thing that causes a reaction (sand, hot pan, glass, etc)
2) receptor cells –> detects stimulus
3) sensory neurones –> pass nerve impulses to spinal cord
4) spinal cord
4.5) relay neurones pass impulses across spinal cord
5) brain
5.5) relay neurones pass impulses across brain
6) spinal cord
6.5) relay neurones pass impulses across spinal cord and to motor neurones
7) motor neurones –> pass impulses to the muscles
8) effector –> muscle or gland
9) response
what do receptor cells do?
change stimulus into an impulse
what is the nervous system made up of?
brain, spinal cord, nerves
3 different types of neurones
-sensory
-relay
-motor
job of sensory neurone
carry electrical impulses from receptor cells to the CNS
job of relay neurone
carry electrical impulses from a sensory neurone to motor neurone
job or motor neurone
carry electrical impulses from the CNS to effectors
where is the nucleus located in a sensory neurone?
middle
where is the nucleus located in a motor neurone?
beginning / end
where are relay neurones found?
CNS only
what is a coordinated response?
brain receives huge number of information from your sensory receptors all the time.
this information is processed and
results in a series of impulses being sent to different parts of the body, producing the required action.
what are voluntary responses
responses that occur as you consciously decide you want to do something (electrical impulses go to the brain)
what are involuntary responses
reflex actions
–> responses that we don’t think about, are automatic
–> don’t go to the brain (just spinal cord)
when do reflex actions occur?
-breathing
-heart rate
-digestion
-danger
–> bright sunshine (squinting)
–> getting cut (pulling hand away)
–> dust in eye (blinking)
–> stress (adrenaline released)
what is a simple reflex arc? (how do reflex actions occur)
1) stimulus –> thing that causes a reaction (sand, hot pan, glass, etc)
2) receptor cells –> detect stimulus
3) Sensory neurones –> pass nerve impulses to the spinal cord
4) spinal cord
5) relay neurones –> in spinal cord, passes nerve impulses across the spinal cord, to motor neurones
6) motor neurones –> passes nerve impulses to muscles (effectors)
7) effectors –> muscle or gland (contract or secrete)
8) response
what does the brain do? [2]
-coordinates body functions
-receives impulses from sensory neurones (optic nerves)
what are effectors?
muscle or gland that does an action in response to the change in the internal or external environment (stimuli)
what does the central nervous system do?
coordinates the response of effectors
what is a stimulus?
any change in the environment to which the body needs to respond
what is a response?
any action, caused by the effector, that helps the organism to avoid the harmful situation
what are receptors?
-found all over the body
-detect change
-initiate a signalling process within the body.
components of the human nervous system
-brain
-spinal cord
-neurones
