A&P 1 Test 4

Where is the epidural space, and what is it filled with mostly?

-The epidural space is the space just outside the dura mater.- Contains adipose tissue but FILLED with cerebral spinal fluid.

Into which space would you place the needle to perform a spinal tap?

-The subarachnoid space. (Inferior to the conus Medullaris.)

The ventral horn can be further divided into what functional regions?

-V.M. ( Visceral Motor)- Motor neurons for internal organs and glands.-S.M.(Somatic Motor)- motor neurons that control skeletal muscle.

What are several functions controlled only by the sympathetic nervous system?

-dilation of blood vessels in skeletal muscle- sweating-erection of body hair control of fat break down contraction of uterus in labor release of hormones from adrenal medulla

Which of these structural types is the most common in the body?

-multipolar are the most common

What happens at the synapse?

-neurons communicate with other cells

Which meninge contains blood vessels that service the spinal cord?

-the Pia Mater

What's the difference between white and gray matter?

-white matter: area with high densities of myelinated axons-grey matter: areas with lots of cell bodies and mostly unmyelinated axons

Describe the cerebral cortex?

.refers to the thin outer layer of the cerebrum

Practice (a): What would the membrane potential be if there was an equal concentration of sodium (Na+) on either side of the membrane?

0 mV

What is the equilibrium potential for potassium (K+)?

0 mV

What are three functions of the cerebellum?

1. Analyzes sensory info 2.Subconsciously adjusts postural muscles to maintain balance 3. Fine-tunes movements of the body 4. Houses procedural memories

What are the four important characteristics of neurons?

1. Excitable- quickly respond to a stimulus by changing the electrical charge across their cell membrane.2. High metabolic rate.3. Extremely long-lived.4. When mature, cannot divide.

Describe the detail the visual pathway beginning with the photoreceptors and ending in the appropriate lobe of the cerebral cortex.

1. Rods and cones2. Bipolar cells3. Ganglion cells4. Axons of ganglion cells make up the optic nerve5. Stimuli in the left visual field of each eye run to the right side of the brain & vice versa (cross over occurs at the optic chiasma)6. From the optic chiasma neurons project to the superior colliculus, thalamus, and occipital lobe

What is meant by hydrocephalus? What often causes it?

"water on the brain" happens when a tumor or other obstruction blocks its circulation, instead the CSF builds up

Describe how information typically flows through a neuron beginning with stimulation of the dendrites and ending with the release of neurotransmitters.

(1)dendrites receive messages from other cells and send the messages to the (2) cell body, which interprets the message and decides what to do, if excited the axon hillock activates the (3) axon, and sends the action potential (4) the action potential causes the release of neurotransmitter across the synapse

Practice (b): What would the membrane potential be if there was little bit more sodium on the inside of the membrane than on the outside?

+5 mV (or any small positive number)

What type of neurons are found in the dorsal horn? in the ventral horn?

- The Dorsal Horn contains sensory neurons- The Ventral Horn contains Motor Neurons

What's the difference between a tract and a nerve?

- Tract: a bundle of similar axons in the CNS(Central nervous system)-Nerve: in PNS (Peripheral nervous system.)

What determines whether a neuron is anaxonic, unipolar, bipolar, or multipolar?

- based off of how many processes come off the cell body

What types of information do different tracts conduct?

--Some conduct pain/temperature information.--Others joint position--Tickle/ Itch--Conscious control of skeletal muscle--subconscious control of postural muscles.

Practice (c): What would the membrane potential be if there was a lot more sodium on the outside of the membrane than on the inside?

-50 mV (or any large negative number)

What is the voltage across the cell membrane of a resting neuron?

-70 mV

What is the major anatomical difference between the ANS and somatic nervous system?

-ANS takes 2 motor neurons to go from CNS to target- Somatic Nervous system takes 1 motor neuron

What is meant by an ascending tract? a descending tract?

-Ascending Tracts: Carry sensory information to the brain.- Descending Tracts: Carry motor commands from the brain to the muscles/glands.

What condition results if the spinal cord is cut at the level of C5 or higher? C6-T1? T1-L1? Below L1? Why?

-C5 or higher: Quadriplegic. C6-T1: some use of the arms. T1- L1: Paraplegic- Below L1: Retain some leg use

Explain how meningitis can kill neurons.

-Inflamation of meninges due to infection--can kill neurons if swelling cuts off blood supply.

The dorsal horn can be further divided into what functional regions?

-S.S. (Somatic Sensory)- Contains sensory neurons for skin, muscle, bone, and joints.-V.S. (Visceral Sensory)- Contains sensory neurons for internal organs.

What are the four key characteristics of a graded potential?

1. changes in membrane potential that decline in strength the farther away you get from the source of stimulation "decline w/ distance" 2. the stronger the stimulus (i.e. initial change in charge), the farther the message will travel 3. occur along dendrites and the cell body (soma)4. can depolarize the membrane or hyperpolarize it

What are the four key characteristics of an action potential?

1. changes in membrane potential that do not decline with distance 2. increasing the strength of the stimulus has NO EFFECT on the strength of the AP 3. AP's occur only along axons4. AP's only cause depolarization

Describe the pathway of taste information starting with the taste cells.

1. cranial nerves send impulses from taste buds to the medulla 2. from medulla, neurons project to the thalamus 3. from thalamus on to the primary somatosensory cortex

What are the four types of neuroglia in the CNS?

1. ependymal cells 2. astrocytes 3. microglial cells 4. oligodendrocytes

What is the function of each type of neuroglia in the PNS?

1. satellite cells- surround neuron cell bodies and control the chemical env. around neurons2. Schwann cells- shield all axons in the PNS from the extracellular fluid

What three chambers make up the cochlea? What type of fluid is found in each chamber? The oval window attaches to which of these chambers? The round window?

1. scala vestibuli (contains perilymph and attaches through the oval window)2. cochlear duct (filled with endolymph)3. scala tympani (contains perilymph and ends at the round window)

What are the three ways to functionally classify neurons? Which of these functional types is by far the most common?

1. sensory neurons2. motor neurons3. interneurons

Explain the steps involved in hearing sound starting with the external ear and ending with the round window.

1. sound waves push on the tympanic membrane which in turn moves the malleus, incus, stapes 2. stapes pushes on oval window which sets perilymph of scala vestibuli in motion 3. the moving perilymph pushes the vestibular membrane down 4. vestibular membrane in turn pushes on endolymph of the cochlear duct 5. endolymph pushes basilar membrane down which bends the hair cells 6. movement of basilar membrane pushes on perilymph of scala tympani 7. finally the pressure is relieved at the round window

What are three major factors that determine the membrane resting potential?

1. the concentration gradients of ions across the neurons plasma membrane (mainly Na+ and K+) 2. the permeability of the membrane to these ions 3. the presence of negatively charged proteins inside the neuron

Give the names of the meninges in order starting with the outermost.

1.) (Outermost) Dura Mater 2.) (Middle) Arachnoid Mater 3.) (Inner Most) Pia Mater.

What are the 3 major functions of the spinal cord

1.) Conduction of Information 2.) Reflexes 3.) Locomotion

What are the three major functions of CSF?

1.)supports the weight of the brain 2.)cushions brain and spinal cord 3.)aids in circulation/transportation of nutrients and wastes

What are three major functions of the basal nuclei?

1.monitor and coordinate slow movements(especially postural movements) 2.decrease rigidity of body (i.e. muscle tone) 3.Suppress useless, unwanted movements

What are the three functions of the hypothalamus?

1.regulates many homeostatic functions(body temp., thirst, hunger) 2.links the nervous and endocrine systems by controlling the secretions of the pituitary gland 3.plays an important role in emotions

practice (h): Place these in order: (1) neurotransmitter release across synapse, (2) action potential, (3) resting potential, (4) graded potential

3, 4, 2, 1

How many primary tastes are there? List all of them.

5sweet, sour, salty, bitter, umami

What is the neurotransmitter released by the parasympathetic nervous system?

Ach

Which gland is an especially important part of the sympathetic nervous system?

Adrenal gland

What two broad categories of receptors are there for NE or E?

Alpha and Beta receptors

What are two classes of drugs used to treat hypertension? Which causes the heart to slow down? Which causes vasodilation of blood vessels?

Alpha-blockers and Beta-blockers-- Beta-blockers--Alpha-blockers

What structures produce CSF? What are these structures made up of?

CSF is produced by choroid plexuses, which are composed of a combination of ependymal cells and capillaries.

Outline the major divisions of the nervous system (there should be at least eight).

Central Nervous System and Peripheral Nerve System ----> Sensory and Motor Division ----> Somatic and Autonomic-----> Sympathetic and Parasympathetic

What are two major divisions of the nervous system?

Central nervous system and peripheral nervous system

Why are two parts of the spinal cord (cervical and lumbar enlargements) especially thick?

Cervical Enlargement: The Cervical Enlargement is especially thick because of the additional neurons needed to service the shoulders/arms. Lumbar Enlargement: The Lumbar Enlargement is especially thick because of the additional neurons needed to service the hip/legs.

What name is given to the end of the spinal cord proper?

Conus Medullaris

Which type of damage would be more life-threatening: damage to the cerebral cortex or the brainstem? Why?

Damage to the brainstem is little chance of survival

What chemical messengers are released by axon of the adrenal medulla?

Epinephrine (aka adrenalin) and norepinephrine (NE)

Describe the general pattern of CSF circulation?

Flows From.... 1.)Lateral ventricles to 3rd to 4th ventricles 2.)then some flows into the central canal 3.)but most passes into subarachnoid space via tiny hole in the 4th ventricle 4.)this CSF then circulates in layer just outside the brain and spinal cord**thus CNS is cushioned both inside and out by CSF 5.)from the subarachnoid space the CSF is absorbed by the arachnoid villi and enters the venous blood supply

What is meant by the functional organization of the gray matter of the spinal cord?

Functional Organization, meaning Divided into 4 regions (Starting with the most posterior) (svvs) 1.) Somatic Sensory -- Contains sensory neurons for skin, muscle, bone, and joints. 2.) Visceral sensory -- Contains sensory neurons for internal organs. 3.) Visceral Motor -- motor neurons for internal organs and glands. 4.) Somatic motor -- motor neurons that control skeletal muscle.

What two major cell types make up taste buds?

Gustatory "taste" cells and supporting cells

Where are the cardiac, vasomotor, and respiratory centers located? What is the function of each?

In the medulla oblongata. 1. Cardiac- adjusts heart rate to meet the body's need 2. Vasomotor- regulates blood pressure by changing artery diameter 3. Respiratory- acts with pons to control rate/depth of breathing

What is the function of the pons?

Involved in subconscious motor control-Contains the pneumotach center *helps to maintain the normal rhythm of breathing-And contains nuclei involved in balance, facial expressions and bladder control

What types of substances con get through the blood-brain-barrier?

It doesn't block everything somethings such as, glucose, have to get to the brain. Some substances can readily pass through phospholipid bilayers can get through easily-gaes, E+OH, small hydrophobics

Practice (e): At the normal resting potential, in which direction, if any, is potassium moving?

K+ diffuses out of the neuron because the inside (-70 mV) is not negative enough to prevent K+ from leaving the cell

If a patient's corpus callosum is severed, can they (without looking at it) tell you what object they are holding in their left hand? Right hand? Why?

Left hand holding apple someone cannot know how to describe because language is on the left side. Right hand you would know how to describe and can say it

What parts of the spinal cord are likely to be damaged in a patient that has lost motor function? lost sensation?

Lost SENSATION:-Dorsal Root Ganglion-Dorsal root-Dorsal Horn-Ascending tracts Lost MOTOR function:-Ventral root-Ventral horn-Descending tracts

List three parts of the limbic system?

Mammillary bodies, Medulla oblongata, Pons

What are three functions of the midbrain? How are the superior and inferior colliculus functionally different?

Midbrain is also involved in consciousness eg, regulates our awareness of pain

What three structures make up the brainstem?

Midbrain, Pons, Medulla oblongata

What is the name of the disorder in which a person's own body attacks its myelin sheaths?

Multiple Sclerosis

Practice (f): At the normal resting potential, in which direction, if any, is sodium moving and why?

Na+ is moving into the cell because it is diffusing down its concentration gradient, because Na+ is attracted to the negative charges inside the neuron

Lack of what vitamin in the mother increases the risk of spina bifida?

Not enough folic acid (Vitamin B)

What is the function of the mammillary bodies?

Nucei in the hypothalamus involved with eating reflexes and behaviors

describe how the brain is protected from both physical and chemical damage?

Physical Protection:-cranial bones-meninges-CSF Chemical Protection:-Blood-Brain barrier (BBB)

What type of neuroglia helps repair damaged axons of the PNS?

Schwann cells

Where are the cell bodies of sensory neurons found? of motor neurons?

Sensory Neurons: Dorsal Root Ganglion Motor Neurons: Ventral Root

What are the three major functions of the nervous system?

Sensory, Integration, Motor

Are the basal nuclei made up of white or gray matter?

Several masses of gray matter located deep within the white matter of the cerebrum.

Contrast the effects of the sympathetic and parasympathetic on a person's alertness.

Sympathetic:- dilates pupils-relaxes ciliary muscle of lens for distance vision Parasympathetic:- constructs pupils-contracts for hear visions

Contrast the effects of the sympathetic and parasympathetic on a person's physical readiness.

Sympathetic:-dilates airways-accelerates heart-constricts blood vessels of most organs and skin-"Fight or Flight"-- prepares body for physical exertion Parasympathetic- constructs airways-slows heart- dilates blood vessels of most organs and skin- "Rest or Algest"

Contrast the effects of the sympathetic and parasympathetic on a person's digestion.

Sympathetic:-inhibits gut movementsinhibits pancreas' release of digestive enzymes-stimulates glycogen breakdown Parasympathetic:- stimulates gut movements- stimulates pancreas' release of digestive enzymes- stimulates synthesis glycogen breakdown

What's the difference between the cauda equina and the filum terminale?

The Filum Terminale is a SINGLE strand of fibrous tissue that extends from the end of the conus medullaris to the coccyx while the Cauda Equina refers to the filum terminale AND the dorsal/ventral roots that extend past the conus.

What foramina must the dorsal and ventral roots pass through to exit the vertebral foramina?

The Intervertebral Foramina

What does the perception of color in the brain depend upon? Explain in class demonstration of afterimages. In particular, why were the colors reversed?

The brains comparing input from the different types of cones; if certain cone photoreceptors are stimulated so much it becomes "bleached"

How does the story of Phinneas Gage illustrate the function of the prefrontal area?

The prefrontal area apparently coordinates information from the association areas of the entire cortex.-plays a major role in personality, decision making, and planning*After Phinneas Gage's accident which injured his prefrontal area his entire personality changes.

Do spinal nerves contain sensory or motor neurons?

They contain both sensory and motor neurons

What determines whether the infant will have a lumbar sac protrusion or not?

Whether or not numerous vertebrae are affected.

What about the cyst determines the degree of physical impairment the infant will have?

Whether or not the cyst contains meninges, CSF, or some of the spinal cord.

How large is the synaptic cleft?

a tiny gap

What goes on in the primary motor cortex?

a.)directs movement b.)if different parts of the primary motor cortex are stimulated, different parts of the body will move*can also be mapped="motor homunculus" c.)part of the body with fine motor control, have a large area of the primary motor cortex devoted to them d.)motor output from the right prim. motor. cortex controls skeletal muscle on the left side of the body and vice-versa

What goes on in the primary somatosensory cortex?

a.)each region within it receives sensory info from a specific part of the body b.)when stimulated, you become consciously aware of the location and intensity of touch, temperature, pressure and pain c.)sensory input from the left side of the body projects to the right SS cortex, and vice-versa d.)in turn, the SS cortex sends sensory info o other parts of the brain for further processing

What is the function of the thalamus in general?

a.)processes sensory info and replys that information to the appropiate location b.)"the gateway" to the cortex c.)nearly all sensory info converges on thalamus*thalamus "edits" the sensory info*then sends it on to the SS cortex and association areas

What is the function of Wernicke's area?

a.)responsible for comprehension of spoken and written words-thus must receive sensory input from temporal and occipital lobes b.)and formulates patterns of speech-then sends "plan" to Broca's area

what is the function of the sympathetic nervous system?

active during stressful situation.

Why does the cerebral cortex have a complex surface?

allows more neurons to be packed into the cranium

What is the significance of the fovea centralis?

area within the macula lutea that has the absolute greatest density of cones (sharpest vision)

What is the function of the ANS in general?

automatically regulates the activity of the viscera (organs), glands, smooth, and cardiac muscles--in response to changing conditions-- occurs subconsciously

What part of the neuron releases neurotransmitter?

axon terminal

where is the axon hillock?

between cell body and axon

What structures make up the CNS?

brain and spinal cord

Which photoreceptor works in bright light? in dim light? Which gives color vision?

bright: cones dim: rods color: cones

What test is routinely performed to screen pregnant women for risk of spina bifida?

by checking their blood for high levels of alpha-fetoprotein.

Describe three major parts of a neuron

cell body, dendrites, axon

What is the largest part of the brain made up?

cerebral cortex and basal nuclei

What three structures make up the inner ear?

cochlea, vestibule, semicircular canals

Which of these chambers houses the organ of corti?

cochlear duct

What is the function of the external ear?

collects and directs sound waves to the tympanic membrane

what is the function of the parasympathetic nervous system?

conserves energy, relaxing, generally has effects opposite of the sympathetic.

what is the function of the voluntary (somatic) nervous system?

control skeletal muscle

what is the function of the involuntary (automatic) nervous system.

controls glands, smooth and cardiac muscle

What is the function of Broca's area?

coordinates the muscles necessary for speech (enables us to produce all the necessary vowel and consonant sounds)

Describe the path that light travels through the eye, beginning with the very front of the eye and ending with the back of the eye.

cornea > aqueous humor > pupil/iris > lens > vitreous humor > retina

What structures make up the PNS?

cranial and spinal nerves

What is depolarization? What is a hyperpolarization?

depolarization: caused by a rapid rise in membrane potential opening of sodium channels in the cellular membrane, resulting in a large influx of sodium ions (becomes less negative, more positive) hyperpolarization: membrane potential becomes negative at the particular spot on the neuron's membrane

What are the three major regions of the ear?

external ear, middle ear, inner ear

What are the symptoms of Raynaud's syndrome? What causes these symptoms?

extremities take on a pale or blue color when sympathetic NS is activated, i.e., by cold or emotions

What do we call collections of neuron cell bodies that occur outside of the CNS?

ganglia (autonomic ganglia)

Describe the distribution of ions, the permeability, and the location of negatively charged proteins in a real neuron at rest.

if we ignore all other ions, the equilibrium potential for K+ is -90 mV ---> K+ continues to diffuse out of the neuron until the inside becomes VERY negative - inside the neuron -70 mV, lots of K+, little Na+, some negatively charged proteins- outside the neuron lots of Na+, little K+ - permeability lots of simple K+ leak channels, few simple Na+ leak channels

What is the function of microglial cells?

important for the immune system

What causes rhodopsin to change shape and ultimately changes ion flow across the rod cell membrane?

in the dark, rods are actually inhibiting bipolar cells1. rhodopsin absorbs faint light 2. which changes the shape and sets off a series of reactions which ultimately change the flow of Na+ across the rod cell membrane 3. this change in charge across the membrane stops the rod from inhibiting the bipolar cells, thus bipolar cells are free to in turn stimulate ganglion cells 4. after the pigment changes shape, it has to be returned to its original shape via an enzyme (and ATP), pigment then bleached

Why are drugs that block muscarinic receptors effective at treating diarrhea?

infection irritates Intestine and rushes feces through too quickly

Place these regions of the brain in order starting from the most complex tasks.

integrative centers, primary cortices, association

Which of these functional types is by far the most common?

interneurons are the most common, accounting for about 90% of our neurons

What is the function of the limbic system?

is the emotional brain

Why is it advantageous to have these primary tastes?

it allows us to choose foods the body needs to function (ex: umami: proteins for building blocks, sweets- energy, salty: electrolytes for nerve function) and avoid dangerous foods (many poisons and spoiled foods are bitter)

What does it mean to say that photoreceptors are "bleached"?

it can't respond to light

What is meant by the neuron membrane's 'resting potential'?

it's when one isn't being stimulated by other cells

What is the function of the pharyngotympanic tube? What is a downside of this tube?

its purpose is to equalize pressure on either side of the eardrum also provides a route for infections to spread from nasopharynx to the middle ear

What side of the cerebrum controls language in most people?

left side in most

What is the function of ependymal cells?

lines cavities of CNS

How do we discriminate loudness versus frequency?

loudness: the louder the sound, the larger the area of the cochlear duct that becomes stimulated frequency: high frequency sounds maximally stimulate the proximal end of the cochlear duct, low frequencies maximally stimulate the distal end of the duct

Describe in detail the auditory pathway beginning with the hair cells and ending in the appropriate lobe of the cerebral cortex.

medulla, inferior colliculus, thalamus, auditory cortex (temporal lobe)

What specific part of the taste cell contains the membrane receptors for chemicals in the foods we eat?

microvilli

Why aren't body parts equally represented in the primary somatosensory cortex?

more cortical space is devoted to parts of the body that are more sensitive

Describe multiple sclerosis. What are its major symptoms?

multiple sclerosis is an autoimmune disease characterized by the gradual loss of myelin in the CNS

What two types of receptors are there for ACh?

nicotinic receptors or muscarinic receptors

What is the most commonly used neurotransmitter of the sympathetic nervous system?

norepinephrine (NE)

Which neurotransmitter is lacking in individuals with Parkinson's disease? What are the symptoms of this disease?

not getting enough dopamine from the midbrain symptoms:-slowness of movement-slurred speech-excess rigidity of body-involuntary, unwanted movement sex. hand tremors, head nodding

What are the four lobes of the cerebral cortex?

occipital, temporal, parietal, frontal

Opposite charges ________ and like (similar) charges _________ each other.

opposite charges ATTRACT and like charges REPEL

Where are the basal nuclei in relation to the cerebral cortex?

other part of the cerebrum.

Spicy foods stimulate which of these other receptors?

pain

Briefly describe Hirschsprung's disease

parasymp. innervation of end of large intestine fails to develop in infants --because that part of gut can't contract and move food along, feces accumulates areas becomes extremely distended (stretched)

Temporal lobe

processes auditory and olfactory information

Parietal lobe

processes sensory info from the surface of the body and joint position

Occipital lobe

processing visual information

What is the function of myelin?

protective covering that surrounds the fibers of axons to protect and insulate these axons

What is the function of CSF (cerebrospinal fluid)?

protects and nourishes the brain and spinal cord

What is the function of oligodendrocytes?

provide support and insulation to axons

What are the three types of cones?

red (long), green (medium), blue (short)

What is the function of astrocytes?

regulate chemical environment

What are the two basic components of the visual pigments? Which component actually absorbs the light? Which component is a derivative of vitamin A?

retinal and opsin opsin (membrane protein) retinal actually absorbs the light, a derivative of vitamin A

What are the two types of photoreceptors? Which is the most common (except at the macula lutea)? Which type contains the pigment rhodopsin?

rods (most common type and pigment rhodopsin) and cones

What is the function of the saccule and utricle versus the semicircular canals?

saccule and utricle: provide balance when person isn't moving and linear acceleration semicircular canals: provide sense of balance also, but when you're moving (speed and direction of head rotation)

What are the two types of neuroglia in the PNS?

satellite cells, Schwann cells

What are the three layers of the eye? The cornea belongs to which of these layers? Which does the iris belong to?

sclera, choroid, retina cornea belongs to the sclera iris belongs to the choroid

What is the function of the pineal gland?

secretes the hormone melatonin, plays a important role in regulating day-night cycles and reproduction

Outline the six subdivisions of the PNS.

sensory (afferent), motor (efferent), voluntary (somatic), involuntary (automatic), sympathetic, parasympathetic

Which ion exerts the larger effect on resting potential, sodium or potassium? Why?

since at rest there are few channels for Na+, resting membrane potential depends mainly on K+

Which of the other five senses has a major influence on our perception of taste?

smell

What is the function of basal cells?

stem cells that replace dead cells

Briefly describe Horner's syndrome

sympathetic innervation to one side of faceis disrupted (due to injury, tumor...)- that side of face reddens with blood because w/o sympathetic the peripheral blood vessels dilate- that side of face doesn't sweat- pupil on that side is noticeably constricted

Practice (d): The equilibrium for potassium (K+) is -90 mV. What does this mean?

that there is no net difference of potassium at this point because the chemical and electrical forces are exactly balanced, in other words, the force due to concentration gradients and the charge gradients are balanced

What is the key to the action potential?

the large number of voltage-gated Na+ channels along the axon

What occurs in the middle ear besides the ossicles and helps prevent damage to the ear caused by loud sounds?

the middle ear communicates with the back of the throat via pharyngotympanic tube; to prevent damage to the ear caused by loud sounds the middle ear contains small muscles which can stiffen the tympanic membrane and prevent excessive movements of the stapes

Practice (g): What effect would a poison that destroys voltage-gated sodium channels have on neurons?

the neurons could not conduct action potentials because they could not allow sodium into the cell

The sympathetic and parasympathetic work cooperatively to regulate which process?

the reproductive organs

What protein helps to maintain the ion concentration gradients? Exactly what does this protein do?

the sodium- potassium exchange pump, type of active transport that uses ATP energy to pump out 3 Na+ for every 2 K+

What type of potential occurs when a stimulus affects a resting neuron?

there's lots of simple K+ leak channels and a few simple Na+ leak channels

Where are taste buds found besides the tongue?

throat and palate

What type of cellular connection is key to the blood-brain-barrier?

tight-junctions between the EPI cells

What are papillae? and what is the relationship between papillae and taste buds?

tiny bumps that cover the tongue's surface; taste buds are embedded in the lateral surfaces of these papillae

What other types of receptors are located in the mouth?

touch, temperature, pain, water

What is the function of the auditory ossicles? List these three bones in order.

transmit sound waves from the tympanic membrane to the oval window malleus, incus, stapes

What is the function of the motor (afferent) division?

transmits motor commands

What is the function of the sensory (afferent) division?

transmits sensory info to the CNS

Which cranial nerve is an especially important part of the parasympathetic nervous system? What does it regulate?

vague nerve (Cranial nerve X)--serves almost all thoracic and abdominal organs

Frontal lobe

voluntary motor activity-speech-thought

Define voltage. What is a synonym for voltage?

when applied to electricity, voltage refers to a difference in charge between two areas synonym: potential

What is a cataract?

when lens (or cornea) becomes cloudy

What is wrong with the vertebrae in an infant with spina bifida?

when vertebral arches fail to form completely.