1 / 22

Sexual Reproduction

This article explores the role of meiosis in sexual reproduction, including the production of gametes (sperm and egg) and the reduction of chromosome number. It covers the stages and outcomes of meiosis in both spermatogenesis and oogenesis, as well as key terms and concepts related to homologous chromosomes, synapsis, and crossing over. The importance of meiosis in generating genetic variations and promoting diversity in offspring is also discussed.

lmazzella
Download Presentation

Sexual Reproduction

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. Sexual Reproduction Involves the fusion of nuclear material from two cells called gametes (sperm and egg)

  2. Meiosis is a special type of cell division by which the gametes (sperm and egg) are produced

  3. Production of sperm is called spermatogenesis and occurs in the testes

  4. Production of egg cells is called oogenesis and occurs in the ovaries

  5. Meiosis is necessary for sexual reproduction to occur because it reduces the number of chromosomes before fertilization takes place • Because of meiosis, the gametes have half the normal number of chromosomes (haploid)

  6. The stages of meiosis are similar to mitosis but there are 2 cell divisions in meiosis and one in mitosis

  7. Meiosis(Spermatogenesis) • In spermatogenesis cell division is equal and results in the production of 4 equal sized sperm cells with flagella

  8. Meiosis (oogenesis) • In oogenesis cell division is unequal, resulting in 1 large egg cell and 3 non functional polar bodies

  9. Terms • Homologous chromosomes: a pair of chromosomes that have the same size and shape and carry the same type of genetic information • One in the pair came from the male and one from the female

  10. Human chromosomes arranged in homologous pairs

  11. Terms • Synapsis- during meiosis homologous chromosomes join together to form tetrads tetrads- group of 4 chromotids

  12. Terms • Crossing over- during synapsis the chromosomes wrap around each other and exchange segments( genetic information)

  13. Crossing Over

  14. Importance of Meiosis • The production of sperm and egg cells that have half the normal number of chromosomes

  15. Importance of Meiosis • Meiosis allows for variations

  16. Variations • Variations in offspring may occur due to the random way in which the chromosomes line up during meiosis

  17. Variations • Variations may occur due to crossing over

More Related