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Meiosis
- Mosquito is used in this 
presentation because it has 3 pairs 
of chromosomes (less drawing!) 
- Humans have 22 pairs of...
Pre: Interphase 
Chromosomes 
replicate 
themselves 
Sister chromatids 
are created 
• 
•
Prophase 1 
Homologous 
chromosome pairs pair 
up together 
Crossing over 
Crossing over- when 
homologous chromosome 
pai...
Metaphase 1 
Homologous 
chromosomes 
separate 
Randomly line up 
in the middle to be 
separated 
• 
•
Anaphase 1 
Spindle fibers 
attach to 
centromeres and 
pull the 
chromosomes 
apart 
•
Telophase 1 
Cells split into 
two daughter cells 
Cytokinesis 
• 
•
Prophase II 
Centrioles move 
into position 
Nuclear 
membranes break 
down 
• 
•
Metaphase II 
Chromosomes 
line up in the 
middle to separate 
•
Anaphase II 
Spindle fibers 
attach to sister 
chromatids 
Chromatids 
pulled apart 
• 
•
Telophase II 
Cells separate 
to create 4 
haploid 
cells/gametes 
•
Essential Points 
Meiosis is used to produce cells for genetic reproduction 
Occurs in germ/sex cells 
Diploid--> Haploid ...
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Meiosis

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Presentation explaining the process of meiosis in cells.

Published in: Science
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Meiosis

  1. 1. Meiosis
  2. 2. - Mosquito is used in this presentation because it has 3 pairs of chromosomes (less drawing!) - Humans have 22 pairs of chromosomes and one pair of sex chromosomes - One set is from the mom, one set from the dad This is a human karyotype. A karyotype lays out all the chromosomes in an organism from longest to shortest in length (numerical order). Shows all the chromosomes and the sex chromosomes from the mom and the dad. This karyotype is from a male because it has both X and Y chromosomes.
  3. 3. Pre: Interphase Chromosomes replicate themselves Sister chromatids are created • •
  4. 4. Prophase 1 Homologous chromosome pairs pair up together Crossing over Crossing over- when homologous chromosome pairs switch their DNA *Crossing over sometimes occurs • • • •
  5. 5. Metaphase 1 Homologous chromosomes separate Randomly line up in the middle to be separated • •
  6. 6. Anaphase 1 Spindle fibers attach to centromeres and pull the chromosomes apart •
  7. 7. Telophase 1 Cells split into two daughter cells Cytokinesis • •
  8. 8. Prophase II Centrioles move into position Nuclear membranes break down • •
  9. 9. Metaphase II Chromosomes line up in the middle to separate •
  10. 10. Anaphase II Spindle fibers attach to sister chromatids Chromatids pulled apart • •
  11. 11. Telophase II Cells separate to create 4 haploid cells/gametes •
  12. 12. Essential Points Meiosis is used to produce cells for genetic reproduction Occurs in germ/sex cells Diploid--> Haploid cells 3 ways variation increases: Homologous chromosomes pair cross-over (Prophase 1) Independent (random) assortment of maternal and paternal chromosomes (how they line up, Metaphase I) Fertilization between random sperm and egg • • • • • • •

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