Chapter 4 section 1

The nrvous system is a complex netwrok of cells that ….. with one another

comunicate

function it controls ….. and … activities and mainatins …. In both ….. and …… enviroments, depends on the …… of signals ….. a ….. and from a …… to another …….

mental, physical, homoostaisis, internal and external, transmision within a neuron , neuron to another cell

neuron is a … cell that is specialized to …. And …… ( transmit) messages in the form of ….. ……

nerve, recieve and conduct, electrical impluses

homiostaisis can be replaced by?

has the ability to monitoir and respond to teh enviroment

neurons transmit information through out the body by 2 things

electrical siganls and chemicals

neuron structiure

Neuron or a nerve cell consist of three esential parts which are

dendrites cell body and axon

The axon also consists iof?

nodes of ranvier myelin sheaths and axon terminal

after contact is amde what is sensed first then taht sensation goes to which side?

dendrites goes towards the cell body and towards the axon terminal after contact

the cell body contains what?

nucleaus and organelles

Discus teh structure of a neuron

Extending from the cell body in diffrent directions are …..-….. …… of the cell called dendrites

membrane covered extensions

denrites recieve information fromn other …. Or other …. And carry the information toward the …. …..

neurons, cells, cell body

cell body the …. Of a neuron and most of its …. Are located inside of teh cell body

nucleaus, organelles

another cell extension the axon is a …. …..-…… ……. That tarbnsmits information away from the cell body

long, membrane bound projection

they carry information away from the cell body in the form of …. … called … …..

electrical signals, action potentials

what are the two extensions of the cell body

the axon and dendrites

a neuron may have a ….. axon or … xon that contact …… other cells

1 branching, several

what advantage is theire if a body cell has many dendries or only one dendrite?

a neuron with many dendrites can recieve inpur from a number of difrent axons alowing many presynaptic neurons

each part of axons

The axons of …. Neurons are covered with a …. Layer known as the mylin sheath, mylin ……. teh axon like rubber around an electrical cord,

Many, lipir , insulates

what does the mylin sheath do?

it speeds up transmission of action potenbtials along the axons

what are those elctrical signals called?

Action potentials

in neurons that are not part of the … or … … cells called ….. cells soround the …. And produce ……

brain, spinal cord, schwan, axon, myelin

so do brain and spinal cords not have myelin then?

They do but diffrent cells produce that

if a body cell doesnt have schwean cells then it wont have? Then it wont have?

Mylin, ranvier nodes

nodes of ranvier are gaps located in the or betwen …… sheath along the length of the axon, which it plays an important role to?

mylin, generate action potential

axon terminal om os located at the end of an axon that …. And …. With …. Cell or. …. Celll or another ……

communicate and contact, muscle cells, gland cells another neuron

Anotehr neuron what part of that neuron?

if it has dendrites then dendrites if no dendrites then cell body

carry information toward the cell body? Away?

dendrites, axon

neuro9ns communicate with other neurons and othjer cells at special junctions called ……

synapses

so basically synapse is the area wherew aht two things meet?

end of axon terminal and end of denrites, or the cell body of another neurons meets another cells

Synapses consist of

presynaptic neurons nerve cell axon end

Synaptic cleft teh area between the celll and the axon

Post synaptic cell the muscle or gland or another neurons

Pre can only be ,,,, but post can be

neuron, neuron muscle gland

neurons ….. do not touch each other or other cells instead a small gap called the …. … is present between teh axon teerminal and recieveing cell

usually, synaptic cleft

at a synapse the transsmitiing neuron is called the ……. Neuron

The recieveingf cell is …. ….

pre synaptic, post synaptic

….. acitivty in the neurons usually causes what? Called? Into the ….. …..

electrical, release of chemicals, neurotransmitter, synaptic cleft

neurotransmitter is a ….. substance that tarnsmits nerve …… acros a …….

chemical, synapse

electricla activity is … neurons but chemical flow is …… neurons

within, between

Why does the signaling acitivty consists of nervous sytem is made up of electrical acitivty within neurons and chemical flow between neurons?

neurotransmitter causes electrical activity ub anotehr neuron and that eelctrical activity 3ill release that 2nd neurons neurotransmitters and so on

Nerve impulses

How did scintests now that neuron function is dependant on electrical activity?

about 200 years ago they remoevd mucle from dead animals and passed electric current trhough it the scientets discioovered taht teh current cause dthe msucle to contacr just as it didi in life since then teh scientest have laerned a great deal about neurons structure, and nuerons affect oteh rparts of the body such as muscles

scienetets have learned that …… function is dependant on ….. …..

neuron, electrical activity

Do all cells have electrical charges?

yes they do

all cells including neurons have electrical charges inside teh cell that is … from the electrical charge outside of the cell

difrent

what is membrane potential

Its the diffrence in …… …. Acros the …. …..

electrical charge, cell membrane

membrane potentials are produced by the?

movement of ions acros the cell membrane

The movement of ions acros teh cell membrane depedns on three thjings

…. Of the ions to …. Through the cell membrane

…. Opf ions inside and outside of the cell

… …. Of the ions as with batteries membrane potentials is expressed as …….

ability to diffuse

Concentration

Electrical charges, voltage

Difrence betwen action potential and membrane potentials is that

membrane potyential is the voltage at any moment

But action piotential is a rapid temporary changem, whena. Neuron is stimulated enough

how do ions diffuse accros a neurons cell membrane?

by passing through protiens thata ct as iion channels

each type of chanal allows ….. …. Ions to pass

only specific

certain channeles are …. Gate dthat is these channerls are open or closed depending on the ….. …..

volrtag, membrane potential

even a small change in …… …. Can affect the permeability of the cell to certain ions

Membrane potentials

As ions enter and move out of the neuron they in tuyrn affect the ….. ……

membranepotenial

membrane potential is teh diffrence ofvoltage between inside and outside dont forget

When in rest outside is …. And inside is …..

when we snese something then outside is …. And inside is …..

positeve, negative

Negative, positeve

if it were negative inside and outside then?

we wont really be able to sense anytrhing

we have resting potential

resting potential is teh electrica;l potentiala cross the .. …. Of a …. Cell or …. Cell when the cell is not active

cell membrane, nerve, muscle cell

is it just nerve cell and musclec ell?

nope its also gland cell

the resting potential in MOST neurons is about

-70 milli volts

concentration of protiens which are negative and potasium and sodium when at rest? what made that k and na diffrence?

in a neuron at rest, protien and potasium r greater inside than outside, bt na is greater outside

Its partly because thej action fo sodium potasium pump that kciks sodium out and brings potasium in

the cell membrane is pemeable to some ions bnut not to otehrs at rest for example

Na ions dont readly diffuse ithroguh the mmebrane sop they acumelate outside teh cell

Negative charged protiens stay inside cuz they are too big to exit

Potasium how ever at rest they can pass freely through the membrane and tend to difuse out of the cell

that freely moving potasium that tends to go outside causes?

Taht charge diffrence between outside and inside where inside is negative is called?

the inside to become negative cuz of the protiens there, and its negative in respect to outside, Resting potential of the membrane

for that reason the …. ….. at rest is called ……..

( not teh cell membrane itself rather its the diffrence accros it)

cell membrane, polarization

The potasium channels are mostly ……

closed

we have action potential

the action potential starts where the …. ….. joins the …..

cell body, axon

1-when a ….. or ….. is stimulated the permeabilty of the neurons membrane changes suddenly

dendrite, cell body

at that point of stimulation the cell membrane becomes permeable to … ions

Na

2 the rush of na ion sinto the cells opens …. Gated sodium channels in the membrane to allow even more na into the neuron

voltage

3- as a result the interior of the nruons cell becomes more …… charged than the exterior this ….. of …… acros the membrane begins an …. ……

negativly, reversal of polarization, action potential

4- voltage gated sodium channels exist along The length of the ….

As a neuron is stimulated and the first small segment of the axon becomes positevly charged, teh change in voltage gated sodium channels open sodium channels in the …. ……of axon membrane

axon , next segment

5- na ions enter driving the voltage in ….. direction and opneing ….. ….. in the next segment of the axon

positeve, sodium channels

6- in this way positeve charges pass down teh axon membrane liek dominoes falling in a row

7- axon potehtaials travel in one direction only … from the cell body where they begin and toward the axon terminal

away

8- shortly after they are opened teh volatge gated for …. Close then voltage gated channels for … openm the result is an abrupt …… flow of … ions, this leads to exterior of the cell again becomes …… charged with respect to the interior of the cell this is called …….

sodiums, ions, , outward, k , positevlty, repolarization

so sodium makes …. Positeve while potasium makes …… positeve

inside, outside

Proper notes

Where is teh action potential really starting?

Its stimulus dendderites/cellbody axoninitialsegment actionpotentialsatrts travelsdownaxo axonterminal

All teh entering of the potasium and etc starts at the initial segments

Denderites stimulated they have their own potential called graded potential if that graded potential ereaches the first segment axon and its able to open lets say 3 channels fo sodium and enough sodium enters to make an action potyential then cuz of that potential more potasium ions open then it starts going down as a domino

And after the domino is past volatge gated channels potasium is pumped out going back to step 1

So when the main streak comes the potasium starts and teh main streak goes the potasium causes the streak there

The first egment of teh axon

Action potential stops( as in its peak) at how much milivolts?

Starts at hiow much?

+40, -60

both depo and repo are parts of ….. potential

action

during depo k and na pumps? repo?

So do we ever have them open at the same time?

na is open k is closed, its opposite, nope

do all channels open at the same time?

no they open in an order

when the na enters it starts opening channels in the? And it starts to drive the potential to?

Next segments, positeve

Sodiums channels are only open during?

Depo

Dont forget during repo and depo k and na close and opne orderly not all at the same time

the neuron ….. egnerate anotehr action potential until ….. …. Is restored

cannot, restign potential

this period duirng which the neuron cannot send a signal is called the ….. period

refarctory

refractory periopd a short period of time after stimulated during wwhich the nerve cannot be ……

stimmulated

after action potential which is teh refractory period potasium more inside and k more outside in this state …. …. And the …… …. Opump help resatblsih the resting concentrations

ion channels, sodium potasum pumps

sodium potasium moves …. Out and moves … inside once the resting potential is restored the neuron is rdy?

Na out k in, for anotehr action potential

neur9ns need a continues suppl;y of …. To keep the sodium potasium pump operating

atp

so what two things that we have studied used atp?

the muscle tissue for reataching, neuronms for sodium potasium pump

action potential is also called? What are the 4 nerve impulses

Nere impulse, 1 polarized, depo, repo, hypo

Action potential starts at how much and ends at how much?

at 55/60 and ends at 70

We have teh big pictiure

Area 1 and area 7 have the same rules

In location two very vew ….. channels open

When does sodium channels begin to close and potasium begin to open?

Communication between neurons

A neuron can communicate with another cell acros the …. …. Only after the … …. Reaches the …. …..

synpaptic cleft, action potential l, axon terminal

afetr action potential reaches teh axon terminal of the pre neuron, teh ……. fuse iwth ……. ……

veciles, pre membrane

when teh vesciles fuse then it means that?

neurotarnsmitters are released

this fussion relases ……. Into the …. …..

neurotarnsmitters, synaptic cleft

the neuro transimmters diffuse acros the synaptic …. and bind to … …. Embedded in the membrane of …. Cell

protien receptors, post

so what have receptor protiens?

w.b.c , muscle cells gland cells neurons

Neurons specifically either the dendrites or cell body