Psl300 - Motor, Ans, & Muscle (Part 1) Questions And Correct Answers

PSL300 - MOTOR, ANS, & MUSCLE (PART
1) QUESTIONS AND CORRECT ANSWERS
IsA2thereA2aA2hierarchyA2toA2brainA2organization?A2-A2Ans--
Yes,A2theA2brainA2isA2veryA2hierarchicallyA2organized,A2inA2thatA2thereA2isA2aA2hierarchicalA
2levelA2ofA2organizationA2ofA2howA2differentA2groupsA2ofA2neuronsA2(nuclei)A2controlA2theA2
motorA2movement

WhatA2isA2theA2simplestA2formA2ofA2motorA2control?A2-A2Ans--
SimpleA2reflexes;A2toA2mediateA2sensoryA2reflexes,A2sensoryA2neuronsA2makeA2synapses
A2withA2spinalA2cordA2motoneurons


AreA2reflexesA2innateA2andA2geneticallyA2determined?A2-A2Ans--
ForA2theA2mostA2part,A2yes;A2manyA2reflexesA2areA2innateA2andA2areA2geneticallyA2determi
nedA2(eg.A2knee-jerkA2reflex)

WhatA2happensA2toA2reflexesA2asA2weA2age?A2-A2Ans--
WhenA2youA2areA2born,A2youA2areA2bornA2withA2allA2kindsA2ofA2reflexes,A2primitiveA2reflexe
s;A2however,A2weA2loseA2aA2lotA2ofA2themA2asA2weA2getA2olderA2(evenA2atA2aA2fewA2months
A2old)A2--
>A2SoA2forA2example,A2inA2newbornA2infants,A2ifA2youA2touchA2theirA2cheekA2theyA2turnA2th
eirA2headA2towardsA2theA2stimulusA2(andA2obviouslyA2thisA2doesn'tA2happenA2toA2youA2now
A2otherwiseA2IA2yourA2headA2wouldA2turnA2wheneverA2IA2touchA2you;A2also,A2ifA2youA2stroke
A2theirA2palm,A2thenA2theyA2willA2grabA2withA2soA2muchA2forceA2thatA2theyA2canA2actuallyA2s
upportA2theirA2ownA2weight,A2butA2obviouslyA2youA2don'tA2doA2thatA2anymore)

IfA2youA2cradleA2anA2infantA2andA2tiltA2toA2stimulateA2falling,A2theirA2armsA2willA2extendA2for
ward

WhatA2doesA2reflexA2mean?A2-A2Ans--"BendingA2back"A2-
A2basicA2elementA2ofA2motorA2control


WhatA2isA2bentA2backA2isA2theA2signalA2aA2sensoryA2signalA2becauseA2itA2allA2startsA2withA2
aA2specificA2sensoryA2stimulusA2whichA2isA2detectedA2byA2theA2sensoryA2receptorsA2--
>A2thisA2informationA2isA2carriedA2intoA2theA2CNSA2byA2theA2sensoryA2afferentsA2andA2isA2q
uicklyA2processedA2withinA2theA2nervousA2systemA2

(weA2knowA2thatA2theA2centralA2nervousA2systemA2isA2theA2integratingA2centerA2thatA2evalu
atesA2allA2incomingA2informationA2andA2selectA2sanA2appropriateA2response)

THISA2ISA2OURA2INPUT

WhatA2isA2theA2formA2ofA2outputA2(reflex)?A2-A2Ans--
OutputA2isA2inA2theA2formA2ofA2actionA2potentialsA2inA2theA2efferentA2neuron(s),A2whichA2ar

, eA2sentA2backA2outA2byA2theA2efferentA2axonsA2toA2produceA2aA2movement,A2aA2specificA2
movementA2(thisA2isA2theA2motorA2response)

HowA2doA2reflexesA2functionA2toA2carryA2outA2aA2specificA2task?A2-A2Ans--
TheyA2functionA2asA2aA2feedbackA2loopA2toA2regulateA2aA2specificA2variable,A2suchA2as,A2s
ay,A2aA2forceA2ofA2contractionA2andA2postureA2theA2limbs,A2etc.

WhatA2doA2somaticA2reflexesA2involve?A2-A2Ans--TheA2skeletalA2muscles

WhatA2areA2theA2elementsA2ofA2aA2reflexA2system?A2-A2Ans--
WeA2haveA2aA2sensoryA2specificA2stimulus,A2activatingA2aA2sensoryA2afferentA2andA2theA2s
ignalA2isA2thenA2carriedA2intoA2theA2CNS,A2eitherA2throughA2theA2spinalA2cordA2orA2toA2theA2
brainstemA2viaA2theA2cranialA2nervesA2--
>A2theA2informationA2isA2thenA2processedA2quicklyA2byA2theA2neuronsA2(theA2interneuronsA
2withinA2theA2CNS),A2andA2finallyA2theyA2signalA2toA2specificA2motorA2neurons,A2toA2sendA2
aA2motorA2efferentA2signalA2outA2toA2theA2muscleA2forA2aA2response

WhatA2isA2aA2monosynapticA2reflex?A2-A2Ans--
HasA2aA2singleA2synapseA2betweenA2theA2afferentA2andA2efferentA2neuronsA2-
A2sensoryA2neuronA2(afferentA2neuron)A2synapsingA2directlyA2toA2aA2motorA2neuronA2andA2
efferentA2neuronA2toA2produceA2aA2responseA2

(anA2exampleA2ofA2aA2spinalA2reflexA2whereA2theA2integrationA2occursA2atA2theA2spinalA2cor
dA2evenA2withoutA2theA2inputA2fromA2theA2brain)

WhatA2isA2aA2polysynapticA2reflex?A2-A2Ans--
HaveA2twoA2orA2moreA2synapsesA2(bothA2synapseA2inA2theA2CNS)

SensoryA2neuronA2synapsesA2withA2anA2inter-
neuron,A2whenA2thenA2synapsesA2withA2theA2motorA2neuronA2toA2produceA2aA2response

WhatA2isA2arguablyA2theA2mostA2importantA2reflexA2inA2theA2motorA2system?A2-A2Ans--
TheA2stretchA2reflexA2(operatesA2atA2subconsciousA2levelA2atA2allA2times)A2-
A2cannotA2maintainA2postureA2withoutA2it


WhatA2isA2theA2adequateA2stimulusA2forA2aA2stretchA2reflex?A2-A2Ans--
StretchingA2ofA2theA2muscleA2(external)A2-
A2passiveA2stretchA2ofA2aA2muscleA2byA2appliedA2loadA2orA2contractionA2ofA2antagonistA2m
uscle

WhatA2isA2theA2responseA2ofA2aA2stretchA2reflex?A2-A2Ans--
TheA2activeA2contractionA2ofA2muscle;A2e.g.A2patellarA2tendonA2reflexA2-
A2onceA2aA2stretchA2isA2sensedA2inA2theA2muscle,A2forA2exampleA2inA2yourA2biceps,A2thisA2
willA2causeA2aA2reflexA2response,A2whichA2isA2veryA2simple;A2theA2stretchA2ofA2theA2bicepsA
2willA2resultA2inA2activeA2contractionA2ofA2theA2bicepsA2(theA2exactA2sameA2muscle)