sexual reproduction. overview of sexual reproduction 2 haploid sex cells (sperm and egg) combine to...
TRANSCRIPT
![Page 1: Sexual Reproduction. Overview of Sexual Reproduction 2 haploid sex cells (Sperm and Egg) combine to form new diploid organism *Sex cells produced via](https://reader036.vdocuments.us/reader036/viewer/2022070307/551a6474550346545e8b5c5e/html5/thumbnails/1.jpg)
Sexual Reproduction
![Page 2: Sexual Reproduction. Overview of Sexual Reproduction 2 haploid sex cells (Sperm and Egg) combine to form new diploid organism *Sex cells produced via](https://reader036.vdocuments.us/reader036/viewer/2022070307/551a6474550346545e8b5c5e/html5/thumbnails/2.jpg)
Overview of Sexual Reproduction• 2 haploid sex cells (Sperm and Egg)
combine to form new diploid organism
*Sex cells produced via meiosis*
n n
2n Fertilized Egg (Zygote)
Egg CellSperm Cell
![Page 3: Sexual Reproduction. Overview of Sexual Reproduction 2 haploid sex cells (Sperm and Egg) combine to form new diploid organism *Sex cells produced via](https://reader036.vdocuments.us/reader036/viewer/2022070307/551a6474550346545e8b5c5e/html5/thumbnails/3.jpg)
Why Study Sea Urchins?• Eggs and sperm are the same size as in
humans
• Fertilization in sea urchins happens outside their bodies - We can watch it happen!
![Page 4: Sexual Reproduction. Overview of Sexual Reproduction 2 haploid sex cells (Sperm and Egg) combine to form new diploid organism *Sex cells produced via](https://reader036.vdocuments.us/reader036/viewer/2022070307/551a6474550346545e8b5c5e/html5/thumbnails/4.jpg)
How Do Sea Urchins Reproduce?
• Sea urchins expel gametes (eggs and sperm) outside their bodies
• We can make this happen in the lab
• We can then watch fertilization under a microscope
![Page 5: Sexual Reproduction. Overview of Sexual Reproduction 2 haploid sex cells (Sperm and Egg) combine to form new diploid organism *Sex cells produced via](https://reader036.vdocuments.us/reader036/viewer/2022070307/551a6474550346545e8b5c5e/html5/thumbnails/5.jpg)
Life of a Zygote
• Zygote goes through series of cell divisions via mitosis
• Also has a larval stage before it reaches adulthood
![Page 6: Sexual Reproduction. Overview of Sexual Reproduction 2 haploid sex cells (Sperm and Egg) combine to form new diploid organism *Sex cells produced via](https://reader036.vdocuments.us/reader036/viewer/2022070307/551a6474550346545e8b5c5e/html5/thumbnails/6.jpg)
Spawning
• Inject urchins with KCl to release eggs and sperm
![Page 7: Sexual Reproduction. Overview of Sexual Reproduction 2 haploid sex cells (Sperm and Egg) combine to form new diploid organism *Sex cells produced via](https://reader036.vdocuments.us/reader036/viewer/2022070307/551a6474550346545e8b5c5e/html5/thumbnails/7.jpg)
Spawning
• Inject urchins with KCl to release eggs and sperm
![Page 8: Sexual Reproduction. Overview of Sexual Reproduction 2 haploid sex cells (Sperm and Egg) combine to form new diploid organism *Sex cells produced via](https://reader036.vdocuments.us/reader036/viewer/2022070307/551a6474550346545e8b5c5e/html5/thumbnails/8.jpg)
Male or Female?
Eggs are orange
Sperm are white
![Page 9: Sexual Reproduction. Overview of Sexual Reproduction 2 haploid sex cells (Sperm and Egg) combine to form new diploid organism *Sex cells produced via](https://reader036.vdocuments.us/reader036/viewer/2022070307/551a6474550346545e8b5c5e/html5/thumbnails/9.jpg)
Collecting the Gametes
Pipette sperm from urchin to tube
![Page 10: Sexual Reproduction. Overview of Sexual Reproduction 2 haploid sex cells (Sperm and Egg) combine to form new diploid organism *Sex cells produced via](https://reader036.vdocuments.us/reader036/viewer/2022070307/551a6474550346545e8b5c5e/html5/thumbnails/10.jpg)
Collecting the Gametes
Let eggs fall into beaker of sea water
![Page 11: Sexual Reproduction. Overview of Sexual Reproduction 2 haploid sex cells (Sperm and Egg) combine to form new diploid organism *Sex cells produced via](https://reader036.vdocuments.us/reader036/viewer/2022070307/551a6474550346545e8b5c5e/html5/thumbnails/11.jpg)
Add Eggs and Sperm to a Slide and Observe Fertilization!
![Page 12: Sexual Reproduction. Overview of Sexual Reproduction 2 haploid sex cells (Sperm and Egg) combine to form new diploid organism *Sex cells produced via](https://reader036.vdocuments.us/reader036/viewer/2022070307/551a6474550346545e8b5c5e/html5/thumbnails/12.jpg)
QuickTime™ and aCinepak decompressor
are needed to see this picture.
![Page 13: Sexual Reproduction. Overview of Sexual Reproduction 2 haploid sex cells (Sperm and Egg) combine to form new diploid organism *Sex cells produced via](https://reader036.vdocuments.us/reader036/viewer/2022070307/551a6474550346545e8b5c5e/html5/thumbnails/13.jpg)
Previously fertilized cells show additional stages of cell
development…
![Page 14: Sexual Reproduction. Overview of Sexual Reproduction 2 haploid sex cells (Sperm and Egg) combine to form new diploid organism *Sex cells produced via](https://reader036.vdocuments.us/reader036/viewer/2022070307/551a6474550346545e8b5c5e/html5/thumbnails/14.jpg)
…as well as larval development
![Page 15: Sexual Reproduction. Overview of Sexual Reproduction 2 haploid sex cells (Sperm and Egg) combine to form new diploid organism *Sex cells produced via](https://reader036.vdocuments.us/reader036/viewer/2022070307/551a6474550346545e8b5c5e/html5/thumbnails/15.jpg)
Some of the preceding pictures, animations, and movies are from the
following websites:
• http://www.stanford.edu/group/Urchin/ani-plus.htm
• http://www.bio.davidson.edu/misc/movies/spermrace.mov