NERVOUS SYSTEM: neuron physiology

Question 1

FUNCTIONAL CLASSIFICATION OF NEURONS

Answer 1

sensory(afferent) neurons
//carry impulses from sensory receptors to the CNS
//cutaneous sense organs
//proprioceptors- detect stretch or tension
motor(efferent) neurons
-carry impulses from central nervous syste, to viscera, muscles, or glands
-interneurons (association neurons)
//found in neural pathways in the central nervous system
//connect sensory & motor neurons
REMEMBER SAD THEN MED

Question 2

STRUCTURAL CLASSIFICATION

Answer 2

-multipolar neurons have many extensions from cell body
-bipolar neurons have once axon & one dendrite
-unipolar neurons have a short, single process leaving the body

Question 3

FUNCTIONAL PROPERTIES OF NEURONS

Answer 3

-irritability-ability to respond to stimuli
-conductivity-ability to transmit an impulse

Question 4

NERVE IMPULSES

Answer 4

-resting neuron
//plasma membrane at rest is polarized
//fewer positive ions are inside the cells than outside the cell, making it negative
-depolarization
//stimulus depolarizes the neuron’s membrane
//depolarized membrane allows sodium (NAT+) to flow inside the membrane
-the exchange of ions initiate an action potential in the neuron

Question 5

NERVE IMPULSES

Answer 5

action potential
-if action potential (nerve impulse starts, it’s propagated over the entire axon)

Question 6

REPOLARIZATON

Answer 6

-potassium ions rush in, which repolarizes the membrane
-sodium-potassum pump, using ATP, changes the original configuration

Question 7

TRANSMISSION OF SIGNAL AT SYNAPSES

Answer 7

-impulses are able to cross the synapse to another nerve
//neurotransmitter is released from a nerves axon terminal
//dendrite of the next neuron as receptors that are stimulated by the neurotransmitter
//action potential is started at dendrite