1. Biology, where multiplication is the same as division
Mitosis and Meiosis
Biology, where multiplication is the same as division

2. Cell Replication All new cells come from existing cells
Cells must divide to allow us to grow, repair damaged tissues and reproduce

3. Chromosomes Segments of DNA containing many thousand genes
Most mammals have 2 sets of chromosomes that code for the same set of characters
Aka are diploid

4. Haploid vs. Diploid 1 set of chromosomes (n) Sperm/egg
Also male bees, stages of plant and fungal life cycle
2 set of chromosomes (2n)
Every cell but the gametes
Stages of plant/fungi life cycle, female bees

5. Homologous Chromosomes
Contain different versions of the same gene (aka alleles)
One inherited from mother, one inherited from father

6. Chromosome Terminology

7. Mitosis Meiosis Types of Cell Division Creates identical cells
Growth, repair, asexual reproduction
Creates haploid cells with half the chromosomes
Creates gametes (sex cells)

9. Interphase
DNA is replicated before both mitosis and meiosis in interphase
Cell also grows bigger and makes proteins necessary for new cells

10. Cytokinesis
Splitting of cell
Occurs after nucleus division (mitosis/meio sis)

11. Mitosis Meiosis Overview One cell division 2 daughter cells
Each contains a single copy of all the chromosomes
Two cell divisions
4 daughter cells
Each contain a single copy of half the chromosomes (no homologous chromosomes)

12. Mitotic Cycle

13. Checkpoints
At certain points the cell cycle is halted until a “go signal” is sent
Cyclin must bind to Cyclin Dependent Kinases
Ensures proper timing of stages, prevents errors and cancers

14. Mitosis

15. Meiosis

16. Meiosis I – homologous chromosomes separated

17. 2 Major Events
Segregation of Homologous Chromosomes
Independent Assortment
One homolog ends up in each gamete, leaving the cell with 23 unpaired chromosomes
Which homolog is inherited for each pair is entirely random

18. Meiosis II – Sister Chromatids Separate

19. Why does it look like some of the chromosomes have been switched?
They have!
During meiosis, some of the homologous chromosomes are exchanged
Increases genetic diversity

20. The Importance of All This
Mitosis creates new identical cells – so every cell in your body is the same
Meiosis creates incredibly unique gametes, increasing genetic diversity
More diversity = more chances of someone surviving

21. You Are A Unique Snowflake
You randomly get 1 of every one of the 23 chromosomes from your father and from your mother
So there were 223 possible combos of sperm and 223 possible eggs
So about 8,388,608 possible sperms could have led to you
So there were about 70,368,470,000,000 possible combinations you could have been (not even counting crossing over!)
You really are one in a trillion!

22. Your Task
In a method of your choosing animate out both mitosis and meiosis (1-3 people)
Focus less on the stage names than on what is occurring over the process
So make a flipbook, gif, video etc. demonstrating the continuous process of the cell cycles
Your initial cell should contain 3 pairs of homologous chromosomes (6 total)
Label them 1A, 1B, 2A, 2B, 3A and 3B. Color code them