Problem 3E

Here are underwater weights in kilograms for 82 male students:

Here are underwater weights in kilograms for 100 female students:

(a) Group each set of data into classes with a class width of 0.5 kilograms and in which the class marks are

0.5, 1.0, 1.5, . . . .

(b) Draw histograms of the grouped data.

(c) Construct box-and-whisker diagrams of the data and draw them on the same graph. Describe what this graph shows.

NervousSystem:TheFundamentalsPart2 4/10/1610:29PM RestingMembranePotential • Restingmembranepotentialliesataround-70mV • Differenceinelectricalchargeacrossthemembrane • Alwaysnegative • Insideofthecellismorenegativethatoutside RoleofIonChannelsInMembranePotential • Leakychannelsarealwaysopen • Gatedchannelsarenotalwaysopen • VoltageGatedchannelsonlyopeninresponsetoavoltagechange TwoFactorsContributetoRMP • Concentrationgradient:ionswillmovedowntheirconcentrationgradient • Electricalgradient:ionswillmovedowntheirelectricalgradient • Balancebetweenthetwoistheelectrochemicalgradient • IonConcentrationinRMP • Moresodiumontheoutsideandmorepotassiumontheinsideofthecell • RoleofPlasmaPermeabilityinRMP • Notpermeabletoproteinanions • VerylittleNa+ispermeable • MostlypermeabletoK+ions • K+andNa+contributemosttoRMP • WhathappenstodisruptRMP • Gradedpotentialswhichoccurindendritesandareincomingsignals(varyinstrength) • Actionpotentialsoccurinaxonsandareoutgoingsignals(allornothing) • ChangesinPolarity • Depolarization:membranepotentialismorepositive • Hyperpolarization:membranepotentialismorenegativethanresting • Repolarization:membranepotentialismorenegativeafterdepolarization • GradedPotentials • Shortandlocalized • Magnitudeanddistancearedeterminedbythestrengthofthestimulus • TwoInstancesofGradedPotentials • ReceptorPotentialorGeneratorPotential:whenasensoryneuronfires • PostsynapticPotential:whenanaxonmeetswiththedendritesofanotherneuron • Axosomatic,axoaxonal,axodendriticsynapses • ActionPotentials • 1.RestingState:nomembranepotentialchange • 2.Na+flowsintothecellbecausethevoltagegatedchannelshaveopened • 3.Repolarization:sodiumchannelsclose,andpotassiumchannelsopen,allowing potassiumtoflowoutofthecell • 4.K+ionscontinuetoleavethecellcausinghyperpolarization • 5.Sodiumpotassiumpumprestoresrestingmembranepotential • Threshold • Actionpotentialsdonotoccurifvoltagedoesnotreach-55mV • Notalldepolarizationscauseactionpotentials • PropagationofActionPotentials • Localvoltagechangecausessodiumchannelstoopen • Thoseopenchannelscausethesodiumchannelsfurtherdowntheneurontoopen • Thishappensallthewaydowntheneuron • Strongerstimuliresultinmoreactionpotentials • RefractoryPeriods • Timewhenanotheractionpotentialcan’thappen • Absolute:actionpotentialwillnotoccur,regardlessofstimulusstrength • Relative:actionpotentialwillonlyoccurwithasuperstrongstimulus • HowFastDoActionPotentialsTravel • Factors:diameterofaxonandamountofmyelination • RoleofMyelinationinActionPotentialVelocity • Innon-myelinatedaxons,actionpotentialshavetoconstantlyregenerate,so conductionisslow • Inmyelinatedaxons,themyelinsheathhousesareasoftheaxonwithnoleakychannels, meaningthevoltageoftheactionpotentialdoesnotdecayasittravels.Thisleadstofast conduction • MultipleSclerosis • Whitebloodcellsattackmyelin • Causespoornervesignaling • Mostlyseeninwomen 4/10/16 10:29 PM 4/10/16 10:29 PM