1. Mitosis
Compare the advantages of sexual and asexual reproduction in different situations.
The student will be able to do the following:
Recognize the steps of Mitosis
Understand Mitosis is a form of asexual reproduction

2. How do little elephants grow up to be BIG elephants?

3. Why do animals shed their skin?

4. Why do our cuts heal?

5. Cell Division—Mitosis
Cell Division —process by which a cell divides into
2 IDENTICAL daughter cells
Why do cells need to divide?
Growth
Repair of damaged tissue
Replacement

6. Understanding the Basics
The original cell is called the parent cell
2 new cells are called daughter cells
Each daughter cell is exactly like the parent cell
Same number of chromosomes
2 Daughter Cells
Parent cell

7. What’s in a name? Where is DNA found??
Long and thread-like DNA in a non-dividing cell is called chromatin
Doubled, coiled, short DNA in a dividing cell is called chromosome
Chromatin
Chromosome
Duplicating

8. Chromosome Structure Chromosome parts: chromatid and centromere
A chromatid is one copy of a duplicated chromosome
A centromere is the place where the chromatids join

9. Numbers are Important!
All somatic (body) cells in an organism have the same kind and number of chromosomes
Examples:
Human = 46 chromosomes
Human skin cell = 46 chromosomes
Human heart cell = 46 chromosomes
Human muscle cell = 46 chromosomes
Fruit fly = 8 chromosomes
Fruit fly skin cell = 8 chromosomes
Fruit fly heart cell = 8 chromosomes
Fruit fly muscle cell = 8 chromosomes

10. Mitosis Cell Cycle Interphase Prophase Metaphase Anaphase
Telophase and
Cytokinesis

11. Interphase Growth 1 (G1) Phase Synthesis (S) Phase
Three phases: G1, S, and G2
Growth 1 (G1) Phase
Normal state of the cell
Carries out daily activities
Synthesis (S) Phase
Preps for another cell division
Centrioles duplicate (for 2 pairs)
DNA is replicated
DNA unwinds into chromatin
Growth 2 (G2) Phase
Cell prepares for division of nucleus
Cell does final check before start ingMitosis

12. Prophase Prepares cell for Mitotic division
Chromotin condense (coils) to chromosomes
Each half of chromosome is called a sister chromatid
Sister chromatids are connected by a centromere
Centrioles move to correct poles
Nuclear envelope dissolves
Spindle Fibers

13. Metaphase Sister chromatids line up in the middle of cell
Centrioles send out spindle fibers to attach to centromere

14. Anaphase Separation begins Spindle fibers shorten
Sister chromatids are pulled apart and go to separate sides of cell

15. Telophase Telophase The sister chromatid halves begin to decondense
New cell nucular membrane forms

16. Cytokinesis Division of the cytoplasm to from 2 new cells
Creates 2 separate daughter cells

17. Summary: Cell Cycle
Interphase Mitosis Cytokinesis
When cells become old or damaged, they die and are replaced with new cells

18. How to Remember The Phases
I-P-M-A-T-C
I Playfully Meow At The Cat

20. Cell Division Control
DNA controls all cell activities including cell division
Some cells lose their ability to control their rate of cell division – the DNA of these cells has become damaged or changed (mutated)
These super-dividing cells form masses called tumors

21. Benign tumors are not cancerous – these cells do not spread to other parts of the body
Malignant tumors are cancerous – these cells break loose and can invade and destroy healthy tissue in other parts of the body (called metastasis)

23. Cancer is not just one disease, but many diseases – over 100 different types of cancers

25. Many organisms, especially unicellular organisms, reproduce by means of cell division – called asexual reproduction – Ex: bacteria