1 / 10

Cells go through two rounds of division in meiosis.

KEY CONCEPT During meiosis, diploid cells undergo two cell divisions that result in haploid cells. Cells go through two rounds of division in meiosis. Meiosis reduces chromosome number and creates genetic diversity. Process of Meiosis: 2 cell divisions, 2 parts: Meiosis I and Meiosis II.

ldick
Télécharger la présentation

Cells go through two rounds of division in meiosis.

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. KEY CONCEPT During meiosis, diploid cells undergo two cell divisions that result in haploid cells.

  2. Cells go through two rounds of division in meiosis. • Meiosis reduces chromosome number and creates genetic diversity.

  3. Process of Meiosis: 2 cell divisions, 2 parts: Meiosis I and Meiosis II Homologous chromosomes Sister chromatids Attached together at the centromere Are duplicates of each other (same information) Separate in Meiosis II • Inherit 1 from each parent • Carry the same or similar information • Separate in Meiosis I homologouschromosomes sister chromatids

  4. Meiosis I occurs after DNA has been replicated. • Meiosis I divides homologous chromosomes in four phases.

  5. Meiosis II divides sister chromatids in four phases. • DNA is not replicated between meiosis I andmeiosis II.

  6. Meiosis animations • http://www.stolaf.edu/people/giannini/flashanimat/celldivision/meiosis.swf • https://www.youtube.com/watch?v=vA8aMpHwYh0Meiosis animations

  7. Meiosis differs from mitosis in significant ways. • Meiosis has two cell divisions while mitosis has one. • In mitosis, homologous chromosomes never pair up. • Meiosis results in haploid cells; mitosis results in diploid cells.

  8. Haploid cells develop into mature gametes. • Gametogenesis is the production of gametes. • Gametogenesis differs between females and males. • Sperm become streamlined and motile. • Sperm primarily contribute DNA to an embryo. • Eggs contribute DNA, cytoplasm, and organelles to an embryo. • During meiosis, the egg gets most of the contents; the other cells form polar bodies.

  9. Crossing Over (Also in Section 6.6) • Often occurs in Prophase I of meiosis • Homologous chromosome pairs are together on one spindle fiber • Called synapsis • Portions of chromosome segments are exchanged • Produces more genetic diversity

  10. Meiosis and crossing over • https://www.youtube.com/watch?v=5x_Rp1mwotQ

More Related