Nervous System Study Guide Plus Vocab and notes
Microglia
act as phagocytic cell within the central nervous system, removing bacterial cells and cellular debris
When the membrane potential reaches threshold volted gated channels open triggering an _____________ at the location
action potential
The local current stimulates the _______________to reach it's threshold
adjacent membrane
absolute refractory
axon membrane can not be stimulated and its the first part of the refractory
divergence
axons may branch at several points diverging axons can amplify an impulse
convergence
axons orginating from different parts of the nervous system leading to same neuron allowing the nervous system to collect process and respond
impulse
bioelectric signals produced by neurons
neurotransmitters
biological messengers produced by neurons
cell body with a process arising from each end one dendrite one axon
bipolar
CNS
brain and spinal cord
The central nervous system is composed of two organs the superior ___ and the inferior ______
brain, spinal cord
The brain is connected to the spinal cord via the ______
brainstem
presynaptic
brings impulse to synapse
Parasympatheic system function
brings the body back to homeostasis after the threat has passed (lowers heart rate and breathing rate and glucose levels) peaceful conditions
collaterals
bunches of axons
brain
contains nerve center assocaiated with sensory functions control of motor functions provide personality
prefrontal areas
control emotional behavior produce awareness of the possible consequences of behavior
Dominant
controls language related activities of speech, writing, reading controls complex intellectual functions requiring verbal analytical and computational skills
sympathetic system function
controls the "fight or flight" response; increases level of glucose, produces goose bumps, heart rate increase, constriction of blood vessels
cerebellum
coordinates voluntary muscle movement, balance and equalibruium maintains posture
polarized
electrically charged to inside - charged with respect to outside
synaptic knob
ending of axon
neurons are
excitable due to response to change in their surroundings
Neruotransmitters are considered to be ___ when increase postsynapitc membrane permeabilitiy to sodium ions will brane the postsynaptic membrane closer to threshold may trigger impulses
excitatory
The right cerebral hemisphere controls the muscles in the right hand responsible for writing
false
Axons that are myelinated conduct impulses at a rate______ than myelinated axons
faster
comprise of parts of the cerebral cortex,diencephalon and other deep nuclei, the ______ represents the area of emotional control
limbic system
Ventricles
line the spaces of the CNS
synaptic potentials
local potiental created by changed in chemically gated ions can depolarize or hyperpolarize the receiveing cell membrane
Na ion
major extracellular cation
K ions
major intercellular + ion and contributor to polarization makes it easier to pass through cell membrane
refractory period
make sure impulse is conducted in one direction limits how many action potentials are generated at one time
meninges
membranes to cover and protect the brain and spinal cord
frontal and temporal
memory
Diencephalon
one of the four major portions of the brain surrounds third ventricle
knee jerk reflex
only uses two neurons initiated by striking the knee tendon
Sodium ions are found in a higher concentration_____ the cell while potassium is more abundant _________ the cell. As a result, NA ions diffuse from ______ and K ions want to diffuse from _____
outside, inside, outside to inside, inside to outside
As cations leave the cell, the membrane potential at that part of the membrane is reestablishing resting membrane potiental This phase of resting potential is called________
repolarization
chromatophillic substance
similar to RER function in protein synthesis
Somatic Nervous system
skeletal onsist of afferent, sensory nerves voulntary muscle movements
lumbar englargement
supplies nerves to lower limbs
curvical enlargement
supplies nerves to upper limbs
satlelite cells
support clusters of neuron cell bodies called galinga
Facial nerves
taste recpetors facial expression tear and salivary glands
true or false the muscles and glands whose activites are controlled by nervous activity
true
Cell body with a single process that divides into two branches
unipolar
Lack myelin sheath
unmyelinated
action potential
varys in speed
Ventral Root
ventral, motor branch of a spinal nerve by which it connects with the spinal cord
hyperpolarized (inhabitory)As these ions enter the cell the cell membrane undergoes ____ with the membrane potential increasing to a peak of approximately +30 Mv
- more than resting potiental
The Na-K pump actively transports ___ Na ions out of the cell for every K ions transported into the cell. This reestablishes the ion distribution and helps maintain the resting membrane potential
3
The Na/K pump transports
3 Na out of the cell and 2 K ions into the cell
suculi
A shallow groove on the surface of the brain
responds to stimulation by the neuron resulting in the behavioral action of the reflex
CNS
The motor divison transmits impulses from the________
CNS to perihperal organs
Medulla Oblogata
In the brainstem controls vital vicsceral actvities
Membrane permeabillity differs for NA and K. The membrane has more channels for ______ than it has for ______. Therefore as the ions follow their diffusion gradient and helps maintain the resting membrane potiental
K and Na
cerebrum
Largest part of the brain reasoning memory and voluntary responses
An action potential results from the opening of __________. These channels open when the membrane potential reaches a level called
Na channel and Threshold
Gaps between neighboring segments of the myelin sheath are____ at these points the axon is not insulated
Nodes of ravier (action potential)
Myelin is formed by two cells (insulator)
Olgendrites in CNS and Schwann cells in the PNS
What cells regenerate
Peripharal Nerves because of neruolemia regenreration is slow
convoltions
Ridge or convolution on the surface of the brain
Oculomotor Nerve
Vision, focus lenses, raise eyelid
fissure
a deep grove on the surface of the brain
Where is CSF located what is it and what does it secrete
a liquid located in the subarachnoid space and the ventricular system around and inside the brain and spinal cord and the chorioid plexus secretes it
Axon Hillox
closest to cell body the trigger zone many closed gated Na channels
action of the sympathetic nervous
increase peristalis of the intestines
neurotransmitters that make reaching threshold less likely are to be _____ because the chance that an impulse will occur
inhabitory
Frontal
movement
Abdueens Nerves
movement of eye
Non-Dominant
nonverbal functions
Sensory neurons (afferent)
relay and carry impulses between neurons in CNS
basal nuclei
relay motor impulses orginating in the cerebral cortex and passing in the brainstem and spinal cord produce dopamine and controls muscular activites
neuroliga cells in PNS
schwann and sattelite
synaptic cleft
space between a synaptic knob and surface of another cell
frontal
speech
Vagus Nerve
speech swallowing
postsynaptic
stimulated by the presynaptic neuron
volts
the potential electical difference between two points
automatic
unconcious
Bundles of myelinated axons form nervous system
white matter
Dendrites
receive input
brainstem
regulates visceral activites and invoulntary, provides basic life support functions breathing and heart stuff
Brocas area
responsible for coordinating complex muscular movements of mouth, tongue and larynx
The _____ is the alert system of the body because of the tracts that provide communication between lower and high brain regions arousing wakefulness when sufficant impulses arrive
reticular formation
Spinal nerves emerges from the cord by two short branches or ____ while lie within the vertebral column
root
The strength of action potiental is ____ The _______ changes
same, frequency
relative refractory
stronger stimulus triggers impulse
The ventricle is continuous with the _____ of the spinal cord and has openings into the ____ of the meninges
subarachnoid space, interventricular formina
ependymal cells
substances diffuse freely between the interstitial fluid of brain and fluid in ventricles
Myelin Sheath
these cells wrapped repeatedly around the axon for a coating and it consists of multiple layers of the cell membrane of the neuroglia cells
local potential
they are graded change in the resting potiental is directly proportional to the intenstity of the stimulus
The _____ is a narrow space in the midline of the brain, just below the corpus callosum
third ventricle
In ______ axons, an impulse is conducted over the entire surface of the axon membrane
unmelyinated
Optic Nerve
vision
occiptial
vision
An action potential arriving at the presynaptic axon terminal causes
voltage gated calcium ions channels to open and calcium ions to diffuse into the synaptic knob
as the peak of action potential is reached the Na channels close and the _____open allowing ions to diffuse out of the cell
voltage gated potassium channels
The nervous system is divided into the _____ which includes the _____ the spinal cord and the _______ nervous system which includes cranial nerves spinal nerves and ganglia
CNS, Brain, PNS
PNS
Cranial and Spinal nerves
Mid-Brain
In the brainstem has auditory and visual reflex center eye and head movements
Pons
In the brainstem helps regulate breathing
Thalamus
In the diencephalon is a relay area for sensory impulses, afferent pathways pass through and synaspe with neurons
These ventricles are connected to the single ventricle below it by two
cerebral aqueduct
The brain consists of the ________ diencephalon,brainstem and ______ the most posterior inferior portion
cerebum, cerebellum
When threshold is reached______ of the initial segment open briefly, allowing _____ to diffuse out of the cell
channels , Na
corpus callosum
collection of myelinated axons which connect cerebral hemispheres
plexus
complex network of spinal cords
somatic
concious,
neuron cell body
cytoplasm cell membrane lysomomes golgi appratus neurofibrils
Therefore, a large myelimated axon will conduct impulses ____ than a thin, unmyelinated axon
faster
axon coated in myelin conduct impulses ______ than unmyeliated axons
faster
Unmyelinated axons, dendrites, neuron cell bodies and synapses are found within the nervous system tissue
gray matter
what is a neuronal pool?
group of neurons that make synaptic connections with each other and work together to perform a common factor
tracts (bundles of neurons)
groups of myelinated nerve fibers in the CNS
parietal lobes
have association areas that help interpret sensory info and aid in understanding speech and chooing words to express thoughts and feelings
Temporal
hearing
The membrane potential activity dips lower than -70 Mv because the K channels do not close quickly enough this is called _______ (more negative)
hyperpolarization
The cycle continues resulting in action potentials traveling down the axon. This is also called ____________ conduction
impulse
Synaptic Transmission
impulse in presynaptic neuron signals postsynaptic neuron
Motor area
impulses are responsible for fine movements in skeletal muscles
Frontal
intellegence
accessory Nerve
muscles of neck and back
degree of change is
portional to intensity of stimulus
Assoicaition area
primary in sensory or motor function
axonal transport
process an axon uses to convey biochemical produced in cell
neurons make
proteins
How many spinal nerves are there?
31 pairs
There are ___ interconnected ventricle in the brain and what are they filled with
4 CSF
Hypothalamus
In the diencephalon links the endocrine to the neural systems, considered the autonomic control center due to regulation of hormonal secretion and heart rate
As cells wrap around the axon cytoplasm ends up in the outermost wrapping of the cell, this contains the organelles and the nucleus
Neurliema
"fight-or-flight" response
an organisms two choices when threatened
occipital lobes
analyzing visual patterns and combining visual images with other sensory experience
The cytoplasm contains many _____ such as phosphate,sulfate, and proteins. These contribute to the negative charge within the cell
anion
The ____ root is the sensory branch of a spinal nerve by which it joins the spinal cord
asending
Glassopharyngeal Nerve
assoicated with tounge and pharnyx for swallowing
reflexes
automatic subconcious , to maintain homestoasis
nerves
bundles of axons
Motor neurons (efferent)
carry impulses form CNS to effectors (muscles and glands) serves as a processing center for the information
axons
carry info away from neurons
Interneurons
carry links between other neurons
Reflex Arcs
carry out reflexes
It is connected to the ventricle below it by a small canal located in the midbrain called the _______
central canal
decending tracts
conduct motor impulses away from the brain
acending tracts
conduct sensory impulses to the brain
The _____ root is the motor branch of a spinal nerve by which it connects it with the spinal cord
decending
As these ions enter the cell the cell membrane undergoes ____ with the membrane potential increasing to a peak of approximately +30 Mv
depolarization
The rate of impulses conduction on an axon is dependent upon myelinated and ______ of the axon
diameter
membrane potential
difference across membrane resting potential and membrane potiental of resting neuron
resting potiental
diffusion not being stimulated to send nerve impulse
Cells of neuron
don't divide
Dorsal Root
dorsal, sensory branch of spinal nerve by which it joins the spinal cord
meninges from superficial to deep
dura mater arachoid mater and pia mater
what is the correct order of menings from superficial to deep
dura meter , arachoid mater, pia mater
conducts the impulse away from the brain or spinal cord and voluntary skeletal muscles
effector
Decisions about responses are made. Then information is conveyed to _____ via the ______ division of the nervous system
effector, motor
Epidemymal Cells
form a membrane that covers the choroid plexuses
The _______ is found posterior to the brainstem and anterior to the _______
fourth ventricle, cerebellum
Neurons found within the central nervous system are classified as _________ structurally these are ___________ neurons
interneurons, multipolar
temporal lobes
interpret complex sensory experiences
sensory areas
interpret impulses from sensory receptors
visual sensations
interpreted in occipital lobe
taste sensations
interpreted in the bases of the central sulci along the lateral sucli
auditory sensations
intrepreted in the temporal lobe
affectors
involuntary smooth and cardiac
gap joint
join epdymal cells together
Parietal
language processing
Another factor affecting impulse conduction rate is the diameter of an axon. The ______ the diameter of an axon, the faster the impulse is conducted.
larger
Triaminal nerve
largest eyes tear glands forehead upper eyelids upper gum upper lip innervate of the muscle of mastication
cerebral cortex
layer of gray matter contains 75% of neuron cell bodies
what hemisphere is more dominant
left
depolarized (excitatory)
less - than resting potiental
cell body
life support
Output from the CNS is carried by ________ neurons. These are multipolar neurons that carry impulses out to structures in the periphery called___________
motor, effectors
key to electrical events in neurons
movement of ions
Trochlear Nerve
moves the eye
cell body with many processes one axon and many dendtires
multipolar
Hyopglossal Nerves
muscles that move tongue
Axons with myelin sheath
myelinated
In _______ axons only the axon membrane exposed the_____ undergo depolarization
myelinated and nodes of ranvier
In a resting neuron the inside of the membrane has more______ charge than the outside of the membrane. The charge difference is called a resting membrane potential
negative
synaptic transmission steps
nerve impulses arrive at axon terminal
Nerve impulses then travel to the CNS along _____. Within the CNS they are __________creating senations memories and emotional reactions.
nerves, integrated
neurons can not exist without what?
neuoliga
Neural tissue consist of two cell types what are they
neurons and nueroliga
withdrawl reflex
occurs when a person touches something painful
occiptial
perception
The sensory division transmits impulses from the_______
perihperal organs to CNS
Frontal
personaility
neurofibrils
proteins
frontal lobe
provide higher intelectual processes
parietal
sensations
Olfactory Nerve
sense of smell
functions of nervous system
sensory imput intergration motor output
Information about our internal and external enviornment is detected by structures called ______ which then convert the information into impulses
sensory receptors
The peripheral nervous system is further subdivided into an afferent ______ division and an efferent ________ division
sensory, motor
Neurons that carry impulses from peripheral receptor to the CNS are classified as ______ neurons. They are typically ____ neurons, though some are bipolar
sensory, unipolar
transverse fissure
separates the cerebrum from the cerebellum
longitudial fissure
separates the left and right cerebral hemispheres
The cell membrane
seperates the electrical charges
synapse
small spaces between a neuron and a cell they communicate with each other
Automatic nervous system (Conscious)
smooth and glands invoulntary movements
The ______ provides two way communication between the CNS and PNS
spinal cord
Astrocytes
star shaped are found in CNS provide support and forming the blood -brain barrier (restrict movement of substances between blood and CNS
nerve impulse
start of action potential along axon not graded all or none response
Neuroliga
the large group of cells within the central and peripheral nervous system serve a supportive function for nervous tissue
Vestbulocohalar Nerve
to maintain equillibruium hearing receptors
An action potential will not occur unless the membrane potential at the _____ reaches a level called _______
trigger zone , threshold