Physio Lab Formal Report EXP 2 SEC-E

Experiment 2: Physiology of Nerve (Section E) Laboratory Report Maria Ronalee Dones, Vergel Vergel Jigs Enriquez, Annielle Cyreen Figueroa, Kym Gonzales

Department of Biologial !ienes College of !iene, "ni#ersity of !anto $omas Espa%a, Manila, &'ilippines

#ario #arious us spe speif ifie ie( ( parts parts t'at t'at fun funti tions ons in

Abstract

The nerve is a specialized cell that  recei eceive vess

and and

tran transm smit itss

elec electr tric ic

sign signal alss

reei# reei#ing ing an( transm transmitt itting ing signal signalss namely namely a2ons a2ons an( (en(ri (en(rites tes**

Den(ri Den(rites tes tran transpo sport rt

throughout the body. Voltage gated channels

eletr eletria iall signal signalss to t'e ell ell )o(y )o(y 3'erea 3'ereass

allow the passage an electric signal called an

a2ons a2ons )rin )ring g sign signal alss a3ay a3ay from from t'e t'e soma soma**

acti action on potent potentia ial. l. In this this exper experim iment ent,, the the

 4eurons are lassifie( in t3o 3ays5 aor(ing

threshold

act action

to num)er of its e2tensions an( )ase( on t'e

 potential, and conduction velocity of the

(ire (iret tio ion n of trans transmi miss ssio ion n of info inform rmat atio ion* n*

nerv nervee wer were dete determ rmin ined ed.. Resu Result ltss are are as

$'ere are t'ree types of neurons aor(ing to

 follows: threshold voltage of the nerve is

t'e num)er of e2tensions* First, is a neuron

!mV

t'at is ompose( of a s'ort e2tension (i#i(e(

volt oltage, ge,

while

the

com compound

maximum

"#$

is

%.%!mV&the %.%!mV&the absolute refractory period of the

into

exam examin ined ed nerv nervee is %.'m %.'mse sess in whic which h the the

funtioning as an a2on an( t'e seon( )ran'

relat elativ ivee

imme immedi diat atel elyy

as a (en(rite* $'is type of neuron is alle(

 follows and lastly, lastly, nerve conduction velocity

 pseu(ounipolar neurons* !eon(, is a neuron

is %.%% m(s.

t'at ontains se#eral (en(rites ra(iating from

refra efract ctor oryy

peri period od

t3o

)ran'es

3it'

one

)ran'

t'e soma toget'er 3it' a single long a2on*

I.

ntro!"ction

$'is neuron is terme( as multipolar neurons*

A neur neuron on is a spei speiali alize ze( ( ell ell t'at t'at

$'e t'ir( an( last type of neuron aor(ing to

forms t'e )asi unit of t'e ner#ous system* +t

t'e t'e amou amount nt of e2te e2tens nsio ions ns are are t'e t'e )ipo )ipola lar  r 

is responsi)le in reei#ing an( transmitting

neuro neurons ns** $'is $'is neur neuron on 'as 'as t3o t3o e2te e2tens nsio ions ns

mess messag ages es in a form form of ele eletr tro o'e 'emi mia all

e2'i e2'i)i )iti ting ng

impulses Morgan - Bloom, .//01* +t 'as

lassi lassifi fiati ation on of neuron neuronss are )ase( )ase( on t'e

simi simila larr

leng lengt' t's* s*

$'e $'e

seo seon( n(

(iretion of information transmission* "n(er 

 potential*

t'is type are sensory neurons, motor neurons

$'is sequene (emonstrates t'e ation

an( interneurons* !ensory neurons reei#e

 potential stimulation* Ation potentials are

signals from sensory organs an( transmit

signifiant

t'ese signals t'roug' t'e a2on into t'e entral

ommuniation among neurons use( )y t'e

ner#ous system* 6n t'e ot'er 'an(, motor 

ner#ous

neurons on(ut signals7information from t'e

&almer - !tuart, .//01* +t is pro(ue( )y t'e

orte2 into t'e spinal or( an( e#entually to

opening an( losing of #oltage'en t'e ma2imum CA& amplitu(e 3as aquire(, inreasing t'e

 4er#es are go#erne( )y t'e allit' an inter#al of .;/mse an( 8.;mse, a

return to a resting potential* $'e relati#e

seon(

pro(ue(*

refratory perio( imme(iately follo3s t'e

Ho3e#er, 3'en t'e inter#al 3as lo3ere( to

a)solute refratory perio(* +n t'e relati#e

0/mse, a seon( ation potential 3as not

refratory perio(, a seon( ation potential

o)ser#e(* +t 3as only 3'en t'e stimulus

an )e pro(ue( at a 'ig'er stimulus*

$'e

t'res'ol(

ation

#oltage

potential

3as

of

#oltage 3as raise( to /mV t'at a seon( ation potential 3as o)ser#e(* >'en t'e inter#al 3as furt'er (erease( to /mse, it nee(e( I;mV stimulus to generate a seon(  potential*

$o

(etermine

t'e

ma2imum

refratory perio( of t'e ner#e, t'e ma2imum amount of stimulus, 0/mV, 3as applie(* A 0/mV stimulus generate( a seon( potential 3'en t'e inter#als 3ere lo3ere( to 8;mse an( *;mse* Ho3e#er, a 0/mV stimulus

A.3. Determination of nerve conduction Velocity $'e on(ution #eloity an )e easily alulate( )y :no3ing )ot' t'e (istane t'e ation potential tra#els or )et3een CA&8 (81 an( CA&. (.1 t'e amount of time it ta:es* Veloity 'as t'e units of (istane per  time or m7s*

+n $a)le , t'e gi#en #alue for t'e (istane )et3een reor(ing eletro(es is

Compoun( Ation &otential  Refratory

/*8m1 )ut sine t'e ta)le )elo3 is in m, /*8

 perio(*

is on#erte( to 8/m* $'e time inter#al

n*(*1* Retrie#e( from

 )et3een CA&8 an( CA&. is /*/s )ut sine

'ttp77333*me(iine*mgill*a7p'ysio

t'e ta)le )elo3 is in ms, /*/ is on#erte( to

7#la)7CA&7refrat*'tm

/ms* $'en using t'e formula Goo(man, B* &*, Harper, C* M*, - Boon, A* J* .//=1* &rolonge( ompoun( musle ation potential (uration in ritial $a)le * Calulation of Con(ution Veloity

illness myopat'y* Musle - 4er#e Musle 4er#e, I/01, 8/I/