The Central Nervous System Flashcards
What are the divisions of the nervous system?
Central nervous system(CNS)- brain and spinal cord
Peripheral Nervous system (PNS)- everything outside the bony encasement,
What is a nucleus?
Collection of neurons inside the central nervous system
What is a ganglion?
collection of neurons outside the CNS.
What is the function and the parts of the Central nervous system?
Made up of interneurons it integrates nervous signals between sensory and motor neurons
What is the function and division of the PNS?
It handles sensory and motor functions. projects into the spine and brain cavity Made up of: somatic nervous system(SNS) autonomic nervous system (ANS)
What is the function of the somatic system?
it is for voluntary movement.
made up of sensory and motor neurons it control mainly skeletal muscle (innervate skeletal muscle)
uses acetylcholine for its neurotransmitter. neurons synapse directly on effector cells
What is the function and division of the autonomic nervous system?
It is used for involuntary muscle responses.
it is divided into the sympathetic and the parasympathetic.It innervate smooth, cardiac and some glands.
where are the neurons of the somatic system located?
motor-ventral horns of spinal ord
sensory- dorsal root ganglion
What is the function of the sympathetic system?
it deals with the flight or fight response. eg increase heart rate. constrict blood vessels.
where are the sympathetic neurons originate?
from the lateral horns of the gray matter of the spinal cord. the post ganglia run up the sides of the spinal cord. they run a long distance
what is gray and white matter?
gray matter is the neuron
white matter- the myelin sheaths that surround the neuron
explain the post and pre-ganglionic neurons.
cells of the ANS uses two neurons
the preganglionic has its cell body in the brain or spinal cord. the axon extends outside the encasement. the first synapse with a second neuron the postganglionic fiber that extends to a visceral effector.
What neurotransmitter does the sympathetic nervous system?
The postganglionic sypathetic fibers secrete epinephrine(adrenaline) and norepinephrine(noradrelinine). they are called adrenrgenic fibers
What is the function of the parasympathetic nervous system?
it has an antagonistic relationship with the sympathetic. it slows breathing heart rate and increase digestive activity
where are the PNS postganglionic fibers located?
they are located near the visceral organs. they travel a very short distance.
