Objec&ves:•  Todaywewill…

– Handbackquizzes.Trackourprogress.– Notes:HumanDevelopment&StemCells– Ar&cleaboutuseofStemCellstoreverseparalysisinmice

•  Sothatwecan…– Usethewords:Fer&liza&on,Zygote,Differen&a&on,StemCellstodescribethestepsofearlydevelopment.

– Weighthemedicalbenefitsofstemcellresearchwithpoten&alethicalconcerns.

BellWork:

1)  Pleasetakeoutthehomeworkyoucompletedtoprepareforthenervoussystem&eyequiz.Addittoyourhomeworklog.Iwillbearoundtostampit!

2)  IamhandingbackyourlastTWOquizzes.PleaseenterthemintoyourUnit5Tracker!

3)  Pleasetakeoutyournotesonthenervoussystem(5-10).Usethesetohelpyoumakecorrec&onsontheNervousSystemsec.onofyourquiz.

OverviewoftheNervousSystem:________NervousSystem _________NervousSystem

• Brain:• SpinalCord:

• Nerves:• SenseOrgans:

DebriefQuiz:

DebriefQuiz:

QuizDebrief:

QuizDebrief:

Review:

Meiosis=aspecialtypeofcelldivisionthatcreatesoursexcells(spermoregg)

Today:

How

?

Fer&liza&on:

A sperm cell unites with an egg cell to form a single cell called a zygote.

HumanDevelopment

Ourbodiesaremadeofabout100trillioncells:

100,000,000,000,000.

Howmanycellsdidwestartwith?

After fertilization, the original zygote undergoes cell division (mitosis) to

produce enough cells.

Zygote

Embryo

Differen&a&on:Whencellsbecome“specialized”(akaturnintodifferenttypesofcells…)

HumanDevelopment

•  Video:hap://www.youtube.com/watch?v=UgT5rUQ9EmQ&feature=related•  Lookfor:

– Crea&onofthezygote– Divisionoftheembryo– Differen&a&onofcellsintheembryo

HumanDevelopment:

QuickCheckforUnderstanding:Pleasechoose“true”or“false”foreachstatement:

a.  Duringdifferen&a&on,acelltakesonaspecialfunc&on.

b.  Differen&a&onisusuallypermanent(inhumans)c.  Anexampleofdifferen&a&onwouldbeasperm

celluni&ngwithaneggcell.d.  Anexampleofdifferen&a&onwouldbean

embryocellbecominganervecell.

HumanDevelopment:

Differentiation!

StemCells:Stemcells=Cellsthathavenotyetdifferen&ated!

Ar&cle:“StemCellsRepairDamagedSpinalCordsinMice”

•  Pleasereadthear&clealoudwithyourpartner.Discusstheques&ons&answerincompletesentences.

TypesofStemCells:

1)  EmbryonicStemCells–  Comefromearlyembryos–  “Pluripotent”

2)  AdultStemCells–  Comefromspecific&ssuesinthebody–  “Mul&potent”

•  Ex:Bonemarrow&ssuecanproduceseveraldifferenttypesofbloodcells.

Poten&alBenefitsofStemCellResearch:

Repairdamaged&ssuethatcannotrepairitself.

Leukemia (cancer of the blood cells)

EthicalDebateoverStemCellResearch:

Destruc&onofhumanembryosvs.

Opportunitytosavelivesbycuringdiseases&repairinginjuries

ExploringSolu&onstoEthicalConcerns:

1)  Getcellsfromembryowithoutdestroyingtheembryo2)  Othersourcesofstemcells(umbilicalcord?)3)  Findawaytoreversedifferen&a&onàcreate“induced”stemcellsfrom

adultcells

Homework:

Pleasefinishques&onsforstemcellar&cle(includinghonorsextension!)