A+P 11-14 Flashcards
what are the functions of the nervous ssytem
sensory input integration homeostasis mental activity control
what are the components of the nervous system
brain, spinal cord, nerves, sensory receptors
What are the subdivisions of the nervous system
central- brian and spinal
peripheral- sensory receptors and nerves
what are sensory recepetors
ending sof hte neurons or specialized cells. detect pain, touch, pressure.
What is a nerve
bundle of axons + sheaths, connects CNS to sensory recpetors, muscles, and glands.
What are the two kinds of nerves
cranial and spinal
What is ganglion
neuron cell bodies outside CNS
What is plexus
axons outside CNS
how many pairs of cranial and spinal nerves are in the nervous system
12, 31
what are the divisions of the PNS
sensory- transmits action potentials from receptors to CNS
motor- transmit action potentials from CNS to effectors
what are the two divisions of the motor system
somatic
autonomic
what are the divisions of the autonomic system
sympathetic
parasympathetic
enteric
which systme is a single neuron
motor division of PNS
what is synapse
axons forming the junction of a neuron with another cell
neuromuscular junction
synapse between the neuron and a skeletal muscle fiber.
what is the two neuron system
autonomic nervous system
why is the autonomic system a two neuron system
CNS to ganglion and Ganglion to effector
What is a sympathetic system
most active during physcial activity
What is the parasynthetic system
regulates resting functions. such as digesting food
What is enteric
plexues in walls of digestive tract.
what is the organization of the nervous system
receptor- sensory NC- CNS- Motor NS- effector
What is purpose of the neurons
receive stimuli and transmit action potentials.
what is neuroglia
support and protect neurons
What is cell body
primary site of protein synthesis
What are dendrites
short, often highly branched.
What are dendritic spines
little protuberances where axons synapse with dendrite.
what is inital segment
beginning of axon
what is trigger zone
site where action potentials are generated.
what is axoplasm
like cytoplasm of the axon
what is axolemma
axons plasma membrane
what are the two forms of axonic transport
away from body
into the cell
how are neurons classified structurally
multipolar- many dendrites with a single axon
bipolar- one dendrite one axon
pseudounipolar- most sendory neurons. single process
how are neurons classified functionally
sensory
motor
interneurons
what are the 4 types of neuroglia of CNS
astrocytes
ependymal
microglia
oligodendrocytes
what are astrocytes
processes form feet- cover sruface of neurons and blood vessels
What do astrocytes promotes
formation of blood brain barrier
what determines what substances can pass from the blood into the nervous tissue of the brain and spinal cord
astrocytes
what do astrocytes allow exchange of
nutrients and waste products between neurons and blood
What do astrocytes prevent fluctuations in blood composition from affecting the brain
What do astrocytes regulate extracellular brain fluid composition.
where are ependymal cells
line brain ventricles and spinal cord central canal
what are choroid plexuses
secrete cerebrospinal fluid.
what are oligodendrocytes
form myelin sheaths if they surrond an axon many times.
what can single oligodendrocytes form
myelin sheaths around portions of several axons.
what are schwann cels
wrap many times around a portion of only one axon- forms myelin sheath
what does myelin do
protects and insulates axons from one another, speedis transmission of APs.
what are unmyelinated axons
not wrapped around the axon.
what is white matter
axons form bundles
what is grey matter
neuron cell bodies and their dendrites are grouped together with very little myelin
what is gray matter on the surface of the brain called
cortex
what are deeper clusters in the brain called
nuclei
what is cluster of neuron cell bodies
ganglion
what are satellite cells
surrond neuron cell bodies in sonsory ganglia.
what do satellite cells provide
support and nutrients to the nueron cell bodies.
what are action potentials
cells produce electrical signals.
what do electrical properties result from
ion concentration difference across plasma membrane
permeability of membrane to ions.
what is the ion concetration of cell due to
the Na/K pump
membrane permeability
what are 4 kinds of gated ion channels
ligand
voltage
touch
temperature
true
true or false
at rest, more K+ and Cl- are moving than Na+
where is K+ in higher concetration
inside the cell
how do ligand gated channels work
ligand binding to receptor protein.
how do voltage gated channels work
when cell is stimulated charge changes- voltage gate ion channels open or close
how do touch receptors work
mechanical stimulation of skin opens gates
how do temperature receptors work
temperature changes in skin opens gates
what is the resting membrane potential
number of charged ions inside=outside.
what is potential difference
electrical charge difference across the plasma membrane is -70 to -90 mV
what happens with the greater charge difference
greater potential difference
what happens if extracellular concetration of K+ increases
depolarization
what happens if extracellular ion concentration decreases
hyperpolarization.
what happens if you chane the concetration of Na+ inside or outside the cell
very little effect
what happens as Na+ diffuses in
depolarization
what are voltage gated Na+ channels sensitive to
Ca2+ concentration.
what is hypocalcemia
uncontrolled concentration of skeletal muscles
increases membrane permeability to Na+
what is a graded potential
a small change in the RMP confined toa small area of the plasma membrane
what do graded potentials result from
ligand binding changes in charge mechanical stimulation teperature changes spontaneous chanfe permeability
whats ummate mean
add onto each other
when is a AP created
local potential reaches threshold
what are action potentials
permeability changes when a local potential causes depolarization of membrane.
what is all on none principle
if stimuli greater than threshold
what are the two phases of action potentials
depolarization
repolarization
what are the two parts of the refractory period.
absolute
relative
what is the absolute
beginning of action potential o near end of repolarization.
what is relative
a stronger than threshold stimulus can initiate another action potential.
what is action potential frequency
number of action potentials produced per unit of time to a stimulis.
what is supramaximal stimulis
stronger than maximal.
what is action potential propagation
AP at one site causes Ap at next location by stimulating voltage gated Na+ channels in adjacent regions of the membrane.
what is synapse
junction between two cells where they communicate with each other.
what are two types of synaptic cells
presynaptic cells
postsynaptic cells
what are connexons
protein tubes
where are electrical synapses found
cardiac and smooth muscle cells.
what does electrical synapses allow for
coordinated contractile activity among groups of cells.
what are synaptic vesicles
Ap causes Ca2+ to eneter cell.
what is postsynaptic membrane
ACh binds to ligand gated Na+ channels.
neurotransmitter substnaces are stored in vesicles located in specialized portions of the
axon
neuromodulators
substance released from neurons
neuromodulators
can influence the likelyhood that an AP in the presynaptic terminal will result in an AP in the postsynaptic cell.
excitory effects on the CNS
increase levels of NE in synaptic cleft.
increase release of norepinephrine from synaptic vesicles in presynaptic neuron.
decrease appetite, increase alertness
enhances ability to concentrate
what is used to treat depression
prozana and zoloft
axoaxonic synapses
axon of one neuron synapses with the presynaptic terminal of another.
presynaptic inhibition
reduction in amount of neurotransmitter released from presynaptic terminal
what is morphine
bind to endophin and enkephalin receptors in presynaptic neurons
what is presynaptic facilitation
increases neurotransmitter released from presynaptic terminal.
what does caffeine stimulate
release of glutamate in the brain.
blocks adenosine receptors and keeps adenosine from doing its job
promotes alertness
convergent pathways
many converge- synapse with smaller number of neurons
divergent pathways
smal number of presynaptic neurons synapse with large number of postsynaptic neurons
what are the segments of the spinal cord
cervical
thoracic
lumbar
sacral
what are the two enlargemnts of the spinal cord
cervical
lumbosacral
what is the conus medullaris
tapered inferior end
What is the cauda equina
orgin of spinal nerves
What is the filum terminale
anchors spinal cord to coccyx
what are meninges
connective tissue membranes
What are the layers of the meninges
dura matter
arachnoid matter
pia matter
what are denticulate ligaments
attach spinal cord to dura matter.
what are the sections between the spinal cord
epidural
subdural
subarachnoid
what is found in the epidural
blood, arealor CT, adipose, spinal nerve roots
what is in the subdural
serous fluid
What is in the subarachnoid
CSF, blood vessels, arachnoid
what is the anterior median fissure
deep cleft partially dividing left and right halves of spinal cord
what is a tract
a collection of axon inside the CNS
what is a nerve
a collection of axon outside the CNS
what is dorsal root ganglion
collections of cell bodies of pseudo unipolar sensory neurons
cell bodies for spinal sensory neurons are located in the
dorsal root ganglia
the spinal cord extends from the
medulla oblongata to the level of the 2nd lumbar vertebra
what is a reflex
an automatic response to a stimulis produced by a reflex arch
what is the basic functional unit of the nervous system
reflex arch
what are the two main kinds of reflexes
automatic and somatic
what are autonomic reflexes
response to stimulis- without concious thought
what are somatic reflexes
remove the body from painful stimuli or keep the body from falling.
what are the components of the relfex arch
sensory neuron
interneuron
motor neuron
effector organ
what are the three types of reflexes
stretch
golgi tendon
withdrawel
what is the stretch reflex
muslces contract due to stretching force applied to them
what is muscle spindle
specialized skeletal muscle fibers that respond to stretch
what are gamma motor neurons
control sensitivity of muscle spindle
what is the golgi tendon reflex
prevents contracting muscles from applying excessive tension to tendons
sudden relaxation of the muscles
what are golgi tendon organs
encapsulated nerve ending located near the muscle tendon junction
what is the withdrawel reflex
removes body limb from pain
what is reciprical innervation
relaxation of extensor muscle when flexor contracts.
what is a crossed extensor reflex
when a withdrawel reflex is iniated in one lower limb, the crossed extensor muscle causes extension of the opposite lower limb.
what do desending tracts do
carry info from the brain to reflexes
what do peripheral nerves consist of
axon bundles
schwann cells
connective tissue
What is epineurium
entire nerve
What is perineurium
axon groups form fasicles
what are endoneurium
individual neurons
what is the name of the covering that covers axon groups to make up fascicles
perineurium
where do the spinal nerves exit from
the sacral foramina
what are the sections of spinal nerves
8 cervical 12 thoracic 5 lumbar 5 sacral 1 coccygeal
what does dorsal ramus do
innervate deep muscles of trunk function in movement of the vertebral column and sensation of the skin near the middle of the back
what does ventral ramus do
innervate intercoastal muscles and skin over thorax
what does communucating rami do
carry axons associated with sympathetic division of the ANS
damage to the dorsal ramus of the spinal nerve results in
loss of sensation and moss of motor function
a collection of spinal nerves that join together after leaving the spinal cord is called a
plexus
what does cervcal plexus innervate
superficial neck structures, skin of the neck, the posterior portion of the head.
what is the ansa cervicalis
loop between C2 and C3
what does phrenic nerve innervate
diaphragm
what is brachial plexus
five ventral rami form three trunks that seperate into six divisions then form cords that give rise to branches
what are the five branches
axillary radial musculocutaneous ulnar median
what laterally rotates the arm
teres minor
what abducts the arm
deltoid
what does radial nerve contain
movements at elbow and wrist. thumb movements
what does musculocutaneous nerve control
movements of flexion at the shoulder, elbow and wrist. supination of the forearm and hand.
what does ulnar nerve control
movements at wrist, fingers , most of intrinsic hand
what is the most easily famged of all spinal nerves
ulnar nerve
what does carpal tunnel come from
damage to median nerve
what happens in carpal tunnel
tingling, burning, numbness in hand, fingers, and middle fingers.
which nerve is involved when you hit your funny bone
ulnar
which nerve is compressed in carpal tunnel syndrome
median
what is the lumbosacral plexus
lumbar and sacral plexus
usually considered together because of close relationship
what four major nerves exit and enter lower limb
obturator
femoral
tibial
common fibular
what does the obturator nerve abduct
the thigh and knee
what movements does the femoral nerve control
movements of hip and knee
what does tibial nerve control
movement of hip, knee, foot, toes
what does common fibular control
anteriro and lateral muscles of the leg and foot
what nerve controls the adductor muscles of the thigh
obturator
what does coccygeal plexus control
motor innervation to muscles of pelvic floor
what is neuritis
inflammation of the nerve from a number of causes. can result in anesthesia
what is neuralgia
nerve inflammation causing stabbing pain. caused by inflammation
what is sciatica
pain radiating down back of thigh
myasthenia gravis
results in fatigue and muscular weakness due to inadequate acetylcholine receptors
what does polio destroy
virus destroys the anterior horn cells
what are the parts of the brain
brainstem
cerebellum
diencephalon
cerebrum
how many pairs of cranial nerves are in the brain
12
what does brainstem do
connects the spinal cord to the cerebrum.
what does oblongata do
pathway for ascending and descending nerve tracts
what is pons
contains ascending and descending nerve tracts. relay between cerebrum and cerebellum.
what is midbrain
contains ascending and descending nerve tracts. visual reflex center.
what is reticular formation
scattered throughout brainstem. controls cyclic activities such as a the sleep wake cycle.
what is cerebellum
control of muscle movement and tone. balance regulates extent of intentional movement
what is thalamus
major sensory relay center. influences mood and movement
what is subthalamus
contians nerve tracts and nuclei
what is epithalamus
condition nuclei responding to olfactory stimulation and contains pineal body
what is hypothalamus
major control center for maintaining homeostasis and regulating endocrine function.
what is cerebrum
conscious perception, thought, and conscious motor activity
what is basal nuclei
control of muscle activity and posture
what is limbic system
autonomic response to smell, emotion, mood and other such functions.
what is discrete nuclei
clusters of gray matter composed mostly of neuron cell bodies.
what does medulla oblongata regulate
heart rate, blood vessel diameter, respiration, swallowing, vomiting, hiccups, coughing, sneezing.
what is pyramids
descinding nerve tracts. inferior fibers decussate one half of brain control opposite side body
what are olives
nuclei involved in functions such as balance, coordination, and mod. of sound
what does the pontine do
relay info between cerebrum and cerebellum
what does pons control
sleep center- iniate REM sleep
what is tectum
four nuclei
what is corpora quadrigemina
form mounds on dorsal surface of midbrain
what is superior colliculi
relfex movements of the head, eyes, and body toward visual, auditory, or tactile stimuli
what is inferior colliculu
auditory pathways
what is a substantia nigra
a nuclear mass. pigmented. interconnected with other basal nuclei of cerebrum
what are cerebral peduncles
descending tracts that carry mot. in from cerebrum to the brainstem and the spinal cord.
what is reticular formation
group of nuclei scattered throughout the brainstem
controls cyclic activities
what system of the brain stem is located in the other three portions of the brain stem
reticular
how does cerebellum communicate with other parts of CNS
fiber tracts called cerebellar peduncles
what are the three cerebellar peduncles
superior- midbrain
middle - pons
inferior- medulla oblongata
what is cerebellum
gray cortex and nuclei with white matter tracts between
what are folia
ridges
what are arbor vitae
white matter.
what are purkinji cells
largest in CNS. inhibitory neurons that receive 200,000 synapses
how many neurons does cerebellar cortex
10^12
what is cerbellar functions
flocculonodular lobe- balance and eye movements
vermis and medial portion of the lateral hemispheres. posture, fine motor coordination.
lateral hemispheres - major portion. works with cerebrum to plan, practice, learn complex movements
the cerebellim communicates with other regions of the CNS through the
cerebellar peduncles
thalamus
lateral portions connected by intermediate mass
what is medial geniculate nucleus
auditory information
what is lateral geniculate nucleus
visual inforamation
what is ventral posterior nucleus
most other types sensory information
what does thalamus influence
mood modification and emotional regulation of anger and rage. connected to limbic system
what is involved in controlling motor functions
subthalamic nuclei
what does pineal gland cause
hypothetically causes sleepiness, helps regulate biological clock, may play role in puberty onset
what is habenular nucleus
responsible for emotional and visceral responses to odors.
what are mammilary bodies
olfactory reflexes and emotional responses to odors
what is infundibulum
a stalk that connects hypothalamus to posterior pituitary gland.
what does hypothamalus control
endocrine system by regulating hormones released by pituitary glands
what does hypothamamus receie input from
internal organs, taste receptors, limbic system, nipples, external genitalia
what is hypothalamus important in
regulation of mood, emotion, sexual pleasure, satiation, rage, and fear.
where does most sensory info synapse in the brain before going on to the cerebrum
thalamus
what does longitudinal fissure divide
two hemispheres
what does lateral fissure seperate
temporal lobe from frontal and parietal lobes
what does central sulcus divide
seperates frontal and parietal lobes.
what is cerebral medulla
the white matter of the brain betweent he cortex and the nuclei. has tracts that connect areas of the cerebral cortex to each other and to other parts of the CNS.
what is basal nuclei
gray matter within the medulla
what is precentral gyrus
primary motor cortex
what is postcentral gyrus
primary somatic sensory cortex
what does frontal lobe control
voluntary motor function, motivation, mood, agression, personality, decision making, and sense of smell.
what is pariental lobe do
reception and evaulation of sensory information.
what does occipital lobe control
reception and integration of visual input
what does temporal lobe control
reception and evauluation for smell and hearing. memory
what does insula control
taste
what are association fibers
connects areas of the cerebral cortex within the same hemisphere
what is commissural fibers
connects one cerebral hemisphere to the other.
what are projection fibers
connects the cerbrum to other parts of the brain and spinal cord.
what is the name of the structure that allows the two cerebral hemispheres to communicate
corpus collosum
where is basal ganglia found
cerevrum, diencephalon and midbrain
what does limbic system control
basic survival functions
interprets sensory input and emotions in general
what does limbic system contain
hippocampus
various nuclei of thalamus
parts of basla nuclei, hypothalamus, olfactory cortex.
what is pia matter bound to
brain
what are the connective tissue partitions
falx cerebri
tentorium cerebelli
falx cerebelli
venous sinuses
what id falx cerebri
anchored to the crista gall of the ethmoid bone.
where is tentorium cerebelli
between cerebellum and cerebrum
where is falz cerebelli
between two cerebellar hemispheres
where is venous sinuses
form were the two layers of dura are seperated.
what is pia matter
thin delicate CT membrane- adhered to brain, follows contours.
What is subarachnoid space
contians web like strands of arachnoid, blood vessesl, CSF
what are four kinds of ventricles
lateral ventricles
third ventricles
interventricular foramina
fourth ventricle
what are lateral ventricles seperated by
septa pellucida
where is lateral venticles
within cerbral hemispheres
where is third ventricle
within diencephalon
where is interventricular foramina
join lateral ventricles with third
where is fourth ventricle
continious with spinal cord, and connected to subarachnoid space by lateral and median apertures.
what is cerebrospianl fluid
similar to blood serum with most of the protein removed.
what does choroid plexus produce
CSF fills ventricles and bathes brain and spinal cord.
What is choroid plexuses composed of
ependymal cells, their support tissue, and blood vessels.
Where is cerbrospinal fluid located.
ventricles.
where is most of the CSF produced and by what structure
choroid plexus, lateral ventricles.
what is brains body weight
2%
what is blood cerebrospinal fluid barrier
arteries in the brain tissue branch into capillaries
what are capillaries made of
epithelial cells attached by tight junctions
what are epithelial cells surronded by
astrocyte foot processes which promote tight junctions.
what do tight junctions do
limit what ubstances can pass through the epithelial cells of capillaries.
what needes mediated transport
water solube molecules.
how do lipid soluble substances pass through brain barrier
diffusion
what are functions of cranial nerves
sensory
somatic motor
parasympathetic
what cranial nerve is involved in chewing food
trigeminal V
what is trigeminal neuralgia
shooting electric pain
sudden onset
what cranial nerve is involved in bells palsy
facial VII
what cranial nerve is not involved in the sense of taste
hypoglossal
what cranial nerves invlved in sense of taste
facial
glossopharyngeal
vagus
what reflexes involve both cranial nerves and brainstem
turning eye toward sudden sound, touch, flashing lights
chewing- movement of tongue pushes food under tooth row.
what is senses
brain receives information about environement and body
what is senssation
consious awareness of stimuli received by sensory receptors
what are steps to stimulation
stimuli from inside or outside body detected by sensory receptors converted into action potentials cerebral cortex of the CNS
what are your two types of general senses
somatic- from outside the body, touch, pressure
visceral- internal organs. pain and pressure.
What are your special senses
smell, sight, taste, hearing , balance
sensory receptor
produces a receptor potential that releases a neurotransmitter. binds to receptors on post synaptic membrane.
what is not a basic type of sense
good sense
what are types od sensory receptors
mechanorecptors- compression, binding, stretching.
chemorecptors- chemicals attached to receptors
thermoreceptors- temp
photorecptors- light, vision
nociceptors- extreme mechanical, chemical, or thermal stimuli
what are simpliest most common sensory receptor
free nerve endings
what are free nerve ending responsible for
temp. detection respond to three types of sensation. cold, warm, pain
what are merkel tactile disks
axonal branches end as flattened expansions
what are hair follicle receptors
hair end organs
responds to slight bending of hair
sensation not very localized, yet it is very sensitive.
which type of receptor responds to light touch and superfical pressure.
merkel disks.
what are sensory areas
primary somatic sensory cortex- posterior to the central sulcis
taste area- inferior end of postcentral gyrus
olfactory cortex- inferior surface of frntal lobe
primary auditory cortex- superior part of temporal lobe
visual cortex- occipital lobe
what is functions of brainstem
all ascending and descending pathways pass through
many reflexes important to survival heart rate, BP, respiration, sleep, swallowing
reticular activating system
controls sleep/wake cycles
RAS receives input from
cranial nerves II V VIII ascending touch sensory pathways descending reurons from the cerbral cortex
where is speech
normally in left erebral cortex
what is wernickes area
sensory speech- understandin what is heard
what brocas area
motor speech- sending messages to muscles to make sounds
what does right cerebral cortex control
muscles and receives sensation from left side of body
right controls
mathmatics and speech
right controls
three dimensional or spatial perception, recognition of faces, musical ability
what is short time memory
information retained for seconds to minutes
what is short term memory
information retained for minutes to days. increased synaptic transmission of glumate.
long term potentiation
neurotransmitter glumate isn presynaptic neuron increases and amount released into the synaptic increases.
glumate receptors on the postsynaptic membrane increases
what are the two parts of long term memory
declarative memory- retention of facts
in hippocampus and amygdaloid
procedural - development of skills
how to get info from short term memory to long term
emotion and moods
repitiion
association
which of the below is not eh best way to store info into long term memory
reading over materail
