meioza
DESCRIPTION
geneticaTRANSCRIPT
![Page 1: Meioza](https://reader030.vdocuments.pub/reader030/viewer/2022012307/5456a529b1af9fe8428b458a/html5/thumbnails/1.jpg)
Diviziunea Diviziunea celularăcelulară -MEIOZA- -MEIOZA-
![Page 2: Meioza](https://reader030.vdocuments.pub/reader030/viewer/2022012307/5456a529b1af9fe8428b458a/html5/thumbnails/2.jpg)
CARACTERISTICI ALE DIVIZIUNIICARACTERISTICI ALE DIVIZIUNII
MITOTICEMITOTICE MEIOTICEMEIOTICE
![Page 3: Meioza](https://reader030.vdocuments.pub/reader030/viewer/2022012307/5456a529b1af9fe8428b458a/html5/thumbnails/3.jpg)
CICLUL CELULARCICLUL CELULAR
Un ciclu celular este reprezentat de o singură alternanţă interfază- diviziune celulară.
INTERFAZA include: faza presintetică, G1 (12 ore) faza “de sinteză” S, (6-8 ore) faza postsintetică, G2(3-4 ore)
DIVIZIUNEA CELULARĂ cuprinde următoarele etape:
profaza; metafaza; anafaza; telofaza.
![Page 4: Meioza](https://reader030.vdocuments.pub/reader030/viewer/2022012307/5456a529b1af9fe8428b458a/html5/thumbnails/4.jpg)
MEIOZA
Între diviziunea I şi II poate exista o perioadă de trecere – interchineza –, dar fără sinteza suplimentară de ADN.
![Page 5: Meioza](https://reader030.vdocuments.pub/reader030/viewer/2022012307/5456a529b1af9fe8428b458a/html5/thumbnails/5.jpg)
![Page 6: Meioza](https://reader030.vdocuments.pub/reader030/viewer/2022012307/5456a529b1af9fe8428b458a/html5/thumbnails/6.jpg)
EEVENIMENTELE MEIOZEIVENIMENTELE MEIOZEI
MEIOZA I
PROFAZA I- cromozomii omologi, bicromatidici:
LEPTOTEN
ZIGOTEN
PACHITEN
DIPLOTEN
DIAKINEZĂ
![Page 7: Meioza](https://reader030.vdocuments.pub/reader030/viewer/2022012307/5456a529b1af9fe8428b458a/html5/thumbnails/7.jpg)
![Page 8: Meioza](https://reader030.vdocuments.pub/reader030/viewer/2022012307/5456a529b1af9fe8428b458a/html5/thumbnails/8.jpg)
(După R. Moore, D. Clark, D. Vodopich, 1998, Botany Visual Resource Library, The McGraw- Hill Co.)
(Dupa Griffiths, et al. 1996, W.H. Freeman and Co.)
synap.mov
![Page 9: Meioza](https://reader030.vdocuments.pub/reader030/viewer/2022012307/5456a529b1af9fe8428b458a/html5/thumbnails/9.jpg)
Crossing Over - variation Crossing Over - variation
nonsister chromatids
chiasmata: site of crossing over
variation
Tetrad
![Page 10: Meioza](https://reader030.vdocuments.pub/reader030/viewer/2022012307/5456a529b1af9fe8428b458a/html5/thumbnails/10.jpg)
METAFAZA I
OR
![Page 11: Meioza](https://reader030.vdocuments.pub/reader030/viewer/2022012307/5456a529b1af9fe8428b458a/html5/thumbnails/11.jpg)
ANAFAZA I
![Page 12: Meioza](https://reader030.vdocuments.pub/reader030/viewer/2022012307/5456a529b1af9fe8428b458a/html5/thumbnails/12.jpg)
TELOFAZA I
![Page 13: Meioza](https://reader030.vdocuments.pub/reader030/viewer/2022012307/5456a529b1af9fe8428b458a/html5/thumbnails/13.jpg)
MEIOZA IIPROFAZA II
![Page 14: Meioza](https://reader030.vdocuments.pub/reader030/viewer/2022012307/5456a529b1af9fe8428b458a/html5/thumbnails/14.jpg)
METAFAZA II-
metaphase platemetaphase plate
![Page 15: Meioza](https://reader030.vdocuments.pub/reader030/viewer/2022012307/5456a529b1af9fe8428b458a/html5/thumbnails/15.jpg)
ANAFAZA II
![Page 16: Meioza](https://reader030.vdocuments.pub/reader030/viewer/2022012307/5456a529b1af9fe8428b458a/html5/thumbnails/16.jpg)
TELOFAZA II
![Page 17: Meioza](https://reader030.vdocuments.pub/reader030/viewer/2022012307/5456a529b1af9fe8428b458a/html5/thumbnails/17.jpg)
Imagini preluate dupa Ralph E. Taggart, http://taggart.glg.msu.edu/bs110/meiosis.htm
![Page 18: Meioza](https://reader030.vdocuments.pub/reader030/viewer/2022012307/5456a529b1af9fe8428b458a/html5/thumbnails/18.jpg)
Imagini preluate dupa Ralph E. Taggart, http://taggart.glg.msu.edu/bs110/meiosis.htm
![Page 19: Meioza](https://reader030.vdocuments.pub/reader030/viewer/2022012307/5456a529b1af9fe8428b458a/html5/thumbnails/19.jpg)
DIVIDIVIZIUNEA MEIOTICĂ- REPREZENTARE ZIUNEA MEIOTICĂ- REPREZENTARE SCHEMATICĂSCHEMATICĂ
![Page 20: Meioza](https://reader030.vdocuments.pub/reader030/viewer/2022012307/5456a529b1af9fe8428b458a/html5/thumbnails/20.jpg)
Mitoza Mitoza ((Vicia sp.Vicia sp.))
© imagini: Johann Wolfgang Goethe-Univ. Frankfurt am Main
profaza metafaza
anafaza telofaza
animatiemitosis.mov mitozaBun.mov
![Page 21: Meioza](https://reader030.vdocuments.pub/reader030/viewer/2022012307/5456a529b1af9fe8428b458a/html5/thumbnails/21.jpg)
Imagini preluate dupa Ralph E. Taggart, http://taggart.glg.msu.edu/bs110/mitosis.htm
![Page 22: Meioza](https://reader030.vdocuments.pub/reader030/viewer/2022012307/5456a529b1af9fe8428b458a/html5/thumbnails/22.jpg)
SpermatogenesisSpermatogenesis
2n=46
humansex cell
diploid (2n)
n=23
n=23
meiosis I
n=23
n=23
n=23
n=23
sperm
haploid (n)
meiosis II
![Page 23: Meioza](https://reader030.vdocuments.pub/reader030/viewer/2022012307/5456a529b1af9fe8428b458a/html5/thumbnails/23.jpg)
![Page 24: Meioza](https://reader030.vdocuments.pub/reader030/viewer/2022012307/5456a529b1af9fe8428b458a/html5/thumbnails/24.jpg)
![Page 25: Meioza](https://reader030.vdocuments.pub/reader030/viewer/2022012307/5456a529b1af9fe8428b458a/html5/thumbnails/25.jpg)
GrowthMitosis I,
Cytoplasmic divisionMeiosis II,
Cytoplasmic division
ovum (haploid)
primary oocyte (diploid)
oogonium (diploid
reproductive cell) secondary
oocyte (haploid)
first polar body
(haploid)
three polar bodies
(haploid)