B13 - coordination & response, hormones, homeostasis Flashcards
roles of nervous system
-coordination
-regulation
define neureons
-nerve cells which transmit electrical impulses
note: CNS = central nervous system
what does CNS consist of
-brain
-spinal cord = control involuntary actions
what does peripheral nervous system consist of
nerves outside of CNS (sensory & motor neurons)
which neurons are found where
sensory & motor - peripheral nervous system
relay - CNS
function of relay neuron
-connect sensory neurons to motor neurones
function of sensory neuron
-carry electrical impulse from receptors to CNS
function of motor neuron
-carry electrical impulses from CNS to effector
where are cell body in sensory, relay & motor neurons
sensory - near the end of neuron
relay - center of neuron
motor - in dendrites
where are dendrites in sensory, relay & motor neurons
sensory - end of neuron
relay - both ends
motor - attached to cell body
part of sensory neuron
-dendrites
-cell body
-nucleus
-axon - inside myelin
-node of ranvier - gap btw myelin
-myelin
-receptor
(direction of impulse is to CNS)
define reflex action
-rapid automatic response to stimulus
-for protection for emergency
-happens before brain is aware
part of motor neuron
-dendrites
-cell body
-nucleus
-axon - inside myelin
-node of ranvier - gap btw myelin
-myelin
-motor end plates
-muscle (effecotr)
part of relay neuron
-dendrites
-cell body
-nucleus
-axon
(no myelin & node of ranvier)
reflex arc
-stimulus
-receptor
-sensory neuron
-relay neuron
-motor neuron
-effector
-response
define receptor
-cell that detects stimulus & generates an electrical impulse
receptor cells & sense organs for light
receptor cells: photoreceptors
sense organs: eye
receptor cells & sense organs for sound, body movement
receptor cells: balance receptors
sense organs: ear
receptor cells & sense organs for chemical (smell)
receptor cells: chemoreceptors
sense organs: nose
receptor cells & sense organs for chemical (taste)
receptor cells: chemoreceptors
sense organs: tongue
define hormnoes
chemical substance produced by a gland (endocrine) & carried by the blood which alters the activity of 1 or more specific target organs
receptor cells & sense organs for temp, pressure, touch, pain
receptor cells: thermoreceptors, pressure/ pain/ touch receptors
sense organs: skin