1. Meiosis
Biology Class- Ms. Fields
9th Grade

2. What is Meiosis, Ms.
Fields?
Good Question!
Meiosis is the process of diploid, multi-cellular organisms
reproducing!
• You start with a diploid cell,
• It must go through cell reproduction (mitosis),
• The two daughter cells then go through meiosis!
• They swap genetic material,
• Split again,
• And you are left with four, secondary daughter, haploid, gamete,
reproduction cells!
• Hurray!

3. Prophase I
– Centromeres appear,
– Spindle Fibers begin to form,
– Centromeres migrate to the two poles,
– Nuclear Envelope begins to disappear.

4. Metaphase I
– Spindle fibers “spout” from centrosomes
– Spindle fibers grab a hold of the PAIR of the homologous chromosomes
– Until Metaphase in mitosis, ONE pole grabs ONE pair of chromosomes

5. Anaphase I
– Spindle fibers bring the pair of chromosomes back to the pole.

6. Telophase I
– Chromosomes reach the destination (finally!)
– Spindle fibers begin to break down,
– Nuclear envelope begins to form.

7. Cytokinesis I
– Nuclei redevelop,
– Cytoplasm develops (with the
organelles)
– Divided into daughter cells (4!!!)
– Haploid, daughter cells:
• Pair of sister chromatids:
– Represents ONE chromosomes

8. Work Cited
• http://www.phschool.com/science/biology_place/biocoach/meiosis/proi.html
• http://www.phschool.com/science/biology_place/biocoach/meiosis/metai.html
• http://www.phschool.com/science/biology_place/biocoach/meiosis/anai.html
LINK TO THE HOMEWORK FOR THIS WEEK!
HOW MEIOSIS WORKS:
http://highered.mcgraw-
hill.com/sites/9834092339/student_view0/chapter11/how_meiosis_works.html
STAGES OF MEIOSIS:
http://highered.mcgraw-
hill.com/sites/9834092339/student_view0/chapter11/stages_of_meiosis.html