eukaryotic life cycles biol 1407. life cycles asexual reproduction sexual reproduction –gametic...
TRANSCRIPT
Eukaryotic Life Cycles
BIOL 1407
Life Cycles
• Asexual Reproduction
• Sexual Reproduction– Gametic meiosis– Zygotic meiosis– Alternation of Generations
Asexual Reproduction• Watch Video #4, binary fission in Paramecium• http://www.microscopyu.com/moviegallery/pondscum/protozoa/paramecium/t1/paramecium04.html• Photo Credit: Courtesy of Richard Allen @ http://www5.pbrc.hawaii.edu/allen/
Gametic Meiosis
• Diploid multicellular organism
• Produces gametes by meiosis
• Gametes = only haploid stage
Gametic Meiosis
• Gametes always fuse to form zygote
• Zygote grows into diploid multicellular organism
Zygotic Meiosis
• Haploid multicellular organism
• Produces gametes by mitosis
• Gametes always fuse to form zygote
Zygotic Meiosis
• Zygote meiosis haploid spores
• Zygote = only diploid stage
• Spores grow into haploid multicellular organisms
Alternation of Generations
• Two generations:– Multicellular
haploid organism– Multicellular diploid
organism– Life cycle
alternates between the two
Alternation of Generations
• Multicellular diploid organism
• Produces haploid spores by meiosis
Alternation of Generations
• Spores grow into haploid multicellular organisms
• Haploid multicellular organism produces gametes by mitosis
Alternation of Generations
• Gametes always fuse to form zygote
• Zygote grows into diploid multicellular organism
Question: Which Type?
The End
Unless otherwise specified, all images in this presentation came from:
Campbell, et al. 2008. Biology, 8th ed. Pearson Benjamin Cummings.