46 notecards = 12 pages (4 cards per page)
What is the nervous system composed of?
Central nervous system (brain & spinal cord)
What does the CNS do?
coordinates and integrates information
What does the PNS do?
bundles of axons which carry information
where does the PNS carry information to?
to the brain or spinal cord( sensory= afferent=incoming)or away from the brain and spinal cord(=motor=efferent=outgoing)
What does AFFERENT mean?
What does EFFERENT mean?
What are the 2 parts to the EFFERENT motor system?
Somatic(voluntary)-to skelatal muscle
Structurally how many types of neurons are there?
3- Bipolar, Multipolar, Unipolar
How many parts to a neuron?
3 parts- cell body, multiple dendrites, ONE AXON
What type of neuron is rare, found in the retina of the eye and olfactory mucosa
What kind of neuron has many branching processes extending from a cell body- all the processes are dendrites except for 1 axon?
What type of neuron has one process (the axon) that extends from the cell body and divides. The distal portion will end in several processes which are classified as dendrites and are the receiving portion of the neuron?
What type of neuron is the first order sensory and bring sensory information into the CNA?
where are sensory and visceral 1st order sensory neurons located?
What carries impulses away from the CNS to effector organs?
lower motor neurons
what are located between other neurons
why do neuron cell bodies appear gray in color?
What is composed of neuron cell bodies and dendrites coming off the cell bodies?
Where is gray matter located in the CNS and PNS?
CNS- in outer gray matter of cerebral and cerebellar cortex, in collections call basal nuclei in brain and inner gray horns of spinal cord
dendrites of 1st order sensory neurons receive sensory input from?
sensory receptors or are stimulated directly (free nerve endings are dendrites-receive pain,heat Etc)
dendrites of multipolar neurons receive input from?
axons of other neurons
How many axons per neuron?
what does the axon do?
transmits the nerve impulse
what part of the neuron is the only part that has voltage regulated gated protein channels for ion passage?
the membrane of the axon part of the neuron
what synapses with a dendrite or cell body of another neuron or synapses with an effector cell (muscle or gland)
What is white matter?
regions dominated by myelinated axons
what is a tract?
collections of ascending and descending axons inside the CNS
what are nerves?
incoming and outgoing axons outside CNS
What are neuroglia?
supporting cells of the nervous system
What are ependymal cells?
form an epithelial type membrane lining spaces inside the brain (ventricles) and the spinal cord which contain CSF
what is the Choroid plexus?
ependymal cells and special brain capillaries
what does the choroid process do?
produce and secrete CSF
what keeps bad stuff from hurting neurons in brain?
what are satellite cells?
structural supporting cells of neurons in ganglia
what are microglia?
wandering phagocytes (eat pathogens, cell waste products)
what are the myelin producing cells in the CNS and the PNS?
myelin is composed mostly of?
what are the Nodes of Ranvier?
gaps between myelin produced by neighboring oligodendrocytes
what happens to the nerve transmission as the lyelin sheath becomes thicker?
The thicker the lyelin sheath the faster the nerve transmission
where are chemically gated ion channels located?
motor end plate of muscle, cell body and dendrite membranes of all neurons
where are chechanically gated ion channels located?
in dendrite membrane of 1st order sensory neurons
where are voltage gated ion channels located?
in muscle and axon membranes only
What are the 2 types of voltage gates?
activation (closed when resting), and inactivation (open at rest)
what ion channel prevents backward transmission?
voltage gated ion channels
what are local depolarizations of a small area of neuron membrane?
where do graded potentials occur?
in sensory receptors in response to stimulus, in dendrites and neuron cell body and motor end plate of muscle