1 / 13

Chapter 8.3

Chapter 8.3. Meiosis. Types of Reproduction. Asexual reproduction Produce offspring with only ONE parent “babies” are identical to parent Sexual reproduction Produce offspring by meiosis and the joining of the sperm and egg “babies” are NOT identical to parents. Meiosis

ouida
Download Presentation

Chapter 8.3

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. Chapter 8.3 Meiosis

  2. Types of Reproduction • Asexual reproduction • Produce offspring with only ONE parent • “babies” are identical to parent • Sexual reproduction • Produce offspring by meiosis and the joining of the sperm and egg • “babies” are NOT identical to parents

  3. Meiosis • New cells have half the number of chromosomes • Gametes • Reproductive cells (sperm and egg)

  4. Key Points • Meiosis must happen so when the sperm and egg join to create a new organism, it has the correct number of chromosomes. • Examples: • Human = 46 • Egg = 23 • Sperm = 23 • Egg + Sperm = baby • 23 + 23 = 46

  5. Meiosis I. (very similar to mitosis) • Prophase I. • DNA coils into chromosomes • Each chromosome lines up with its homologue (the similar chromosomes) • Synapsis: pairing of homologous chromosomes • Each pair is called a tetrad • Crossing-over: may occur where pieces of one chromosome break off and attach to the other chromosome  genetic recombination

  6. Metaphase I. • Tetrads line up along the middle of the cell

  7. Anaphase I. • Each homologous chromosome of each tetrad moves to opposite ends of the cell

  8. Telophase I. • Cell divides creating 2 new cells each with a haploid number of chromosomes (1/2 the original number of chromosomes, but 2 copies of each)

More Related