Process of meiosis - PowerPoint PPT Presentation

Process of meiosis
Download
1 / 11

  • 30 Views
  • Uploaded on
  • Presentation posted in: General

Process of meiosis. CSCOPE Unit 08 Lesson 02. Asexual vs. sexual reproduction. Asexual vs. sexual reproduction. What is the advantage of an organism that reproduces sexually rather than asexually?

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.

Download Presentation

Process of 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.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Process of meiosis

Process of meiosis

CSCOPE

Unit 08

Lesson 02


Asexual vs sexual reproduction

Asexual vs. sexual reproduction


Asexual vs sexual reproduction1

Asexual vs. sexual reproduction

  • What is the advantage of an organism that reproduces sexually rather than asexually?

    • An organism that reproduces sexually will have more genetic diversity than one that reproduces asexually.


Meiosis i

Meiosis i

  • Four Phases:

    • Prophase I

    • Metaphase I

    • Anaphase I (and)

    • Telophase I

  • Genetic diversity results from meiosis I.


Prophase i

Prophase I

  • Homologous (same) chromosomes pair (synapsis)

  • Homologous pairs called bivalents—two chromosome with four chromatids

  • Nuclear membrane dissolves

  • Chromosomes attach to spindle fibers and begin to move


Metaphase i

Metaphase I

  • Homologous chromosomes (bivalents) line up at the equator to form tetrads.

  • Random orientation results in diversity.

  • 50/50 chance of getting either parent’s homologue for each chromosome

Tetrad


Anaphase i

Anaphase I

  • Homologous chromosomes separate.

  • Chromosomes with TWO chromatids move to opposite poles.

  • Daughter cells will have 23 chromosomes (haploid) but with two chromatids.


Telophase i

Telophase I

  • Nuclear membrane begins to reform

  • Cell may quickly move to meoisis II


Meiosis ii

Meiosis II

  • Similar to mitosis BUT no synthesis phase (no DNA replication)

  • Chromatids are NOT identical because of crossing over (recombination).

  • Separates chromatids and produces two daughter cells with 23 chromosomes that have one chromatid each


Important concepts

Important Concepts!!!

  • Crossing Over: Exchange of genetic information between homologous chromosomes that results in recombinant chromosomes and genetic diversity


Important concepts1

Important Concepts!!!

  • Independent Assortment: Chromosomes randomly line up during metaphase I, and there are various ways that the homologous chromosomes may line up—again resulting in genetic diversity

http://www.mhhe.com/biosci/ap/ap_prep/bioD6.html


  • Login