Meiosis–InternetLesson

Inthisinvestigation,youwillviewsitesthatillustratetheprocessofmeiosis.Foreachsiteanswerthequestionsassociated.

Site1–Lew-Port’sMeiosisPage

Goto

1.Howmanychromosomesdoesthecellinthisanimationstartwith?

2.Thehomologouspairsarerepresentedbysimilar

3.Copiesofchromosomesareheldtogetherbythe

4.Eachchromosomefindsits

5.Draw“crossingover”–usingyourpenciltoshadeintheareasthatexchangeparts.

6.Howmanychromosomesareateachpoleofthecell?

7.Duringmeiosis2,chromosomeslineupagainalongthecell’s

8.Onlycopyofeachchromosomemovestowardthepoles.Whichmeansonly

chromosomesoftheoriginalsix.

9.Newmembranesformaroundeach

10.Eachcelldivides,formingatotalofcells.

Site2–SumanasInc.,AnimationofMeiosis

GototheSumanaswebsiteclickonGeneralBiology,thenclickonMeiosis

11.Readtheintroduction. Explainthedifferencebetweensexualandasexualreproduction.

ClickonNarrated

12.DNAreplicationtakesplacewhen?

13.Meiosisconsistsoftwocell divisions:&

14.Centrosomes(akacentrioles)migrateto

15.Thepairingofhomologouschromosomesiscalled:

16.Crossingoverpointsarecalled

17.WhathappensinmetaphaseI

18.WhathappensduringanaphaseI

19.Whatisinterkinesis?

20.InprophaseII,eachcellsis[diploid/haploid](circle)

21.InmetaphaseII,chromosomeslineupin[single|double]file.

22.WhathappensduringtelophaseII?

23.(ClicktoConclusion).Eachofthefourdaughtercellsproducedbymeiosisis[identical/unique]

ClickonQuiz

24.Withrespecttomeiosis,whendoesDNAreplicationoccur?

25.Whendoescrossingoveroccur?

26.Duringwhichphasedochromosomeslineupalongtheequator?

27.Duringwhichphasedoesthenuclearmembraneformaroundthechromosomes?

Site3–BiologyinMotion-Meiosis

Goto

28.Therearetwowaysinwhichthechromosomescanendupaftermeiosis.Sketchthetwowaysandindicatebycolorthechromosomes(usethefollowingcolorcodes:Purple,DarkPurple,Green,Darkgreen)

Possibility1Possibility2

Site4: PBS:Mitosisvs.Meiosis

29.Afterviewingtheanimation. Filloutthechartbelow,byplacingacheckintheboxorboxes.

Event / MitosisOnly / MeiosisOnly / Both
Twocelldivisions
Centriolesappear
Chromosomespairup
Spindlefibersform
Cytokinesis
Fourdaughtercells

PhasesofMeiosis

NameofPhase / Description
1. / Homologouschromosomespairupandformtetrad
2. / Spindlefibersmovehomologouschromosomestooppositesides
3. / Nuclearmembranereforms,cytoplasmdivides,4daughtercellsformed
4. / Chromosomeslineupalongequator,notinhomologouspairs
5. / Crossing-overoccurs
6. / Chromatidsseparate
7. / Homologslineupaloneequator
8. / Cytoplasmdivides,2daughtercellsareformed