1. Anatomy and Physiology
Cell Reproduction
The Cell Cycle: Mitosis

2. The Cell Cycle
The series of changes that a cell undergoes from the time it forms until the time it divides.

3. Interphase Stages of Interphase
Period between cell divisions when a cell is carrying on its normal functions and is preparing for division.
Stages of Interphase
G1 - Growth phase - cells grow and develop, rapid growth and protein synthesis.
S - Synthesis phase - DNA replication occurs.
G2 - Growth phase - centrioles replicate, cell prepares for cell division.

4. Mitosis
Division of a somatic cell to form two genetically identical nuclei or daughter cells.
P.M.A.T
Prophase
Metaphase
Anaphase
Telophase

5. Mitosis Somatic Cells - body cells, chromosome number is constant.
Chromosomes exist in pairs.
Ex. We have 23 pairs of chromosomes or 46 chromosomes.
Called diploid or 2N (two homologous copies of a chromosome)
Each pair of chromosomes carries the genetic information for the same trait - Homologous.

6. Chromosome Structure Sister Chromatids Centromere
Duplicated chromosome made in S phase of interphase.
Centromere
Holds sister chromatids together.

7. Chromatin Chromatid Chromosomes
Nucleus
Chromatin
All the DNA/proteins in nucleus … condenses to form chromosomes during Mitosis
Chromatid
Sister chromatid
Sister chromatid
Chromosomes
Condensed chromatin .. Either 2 sister chromatids or 1 chromatid

8. 4 Stages of Mitosis: Prophase
Chromatin in the nucleus condenses to form visible chromosomes.
Nuclear membrane breaks down.
Nucleolus disappears.
Centrioles move to opposite sides of the cell.
Microtubules form spindle fibers attached to centrioles.

9. 4 Stages of Mitosis: Metaphase
Chromosomes align in the center of the cells and attach to the spindle fibers by their centromeres.

10. 4 Stages of Mitosis: Anaphase
Centromeres separate- sister chromatids move to opposite ends (poles) of the cell.
The individual sister chromatids are now call individual chromosomes.

11. 4 Stages of Mitosis: Telophase
Like prophase in reverse.
Chromosomes uncoil.
Nuclear membrane reforms around chromosome set.
Nucleoli become visible inside nucleus again.
Spindle fibers break down.

12. Cytokinesis: Cytoplasmic Division
Considered a separate stage.
Cell membrane pinches in on itself until 2 daughter cells are formed.
Cytokinesis

13. Cancer is the uncontrolled growth and division of cells.
Regulation
Internal and external factors regulate cell division.
Cancer is the uncontrolled growth and division of cells.
Cancer cells can kill an organism by crowding out normal cells, resulting in the loss of
tissue function.

14. Cancer Benign Malignant cancer cell bloodstream normal cell
metastasize
Benign
Malignant

15. Causes of Cancer Internal Factors Inheritance Mutations
External Factors
Carcinogens are substances that are known to produce and promote the
development of cancer.
Radiation
Chemical
Viruses
Skin Cancer

16. Mitosis
Review

18. Cell Differentiation
The process by which cells develop different structures and specialized functions.
Controlled by the activation of certain genes.

19. Stem Cells
A precursor cell that can be triggered by genes to become any type of cell.

20. Meiosis Why does it take place?
Forming of gametes which are haploid cells
Where does it take place?
Reproductive organs – Male = testes
Female = ovaries 20

21. 46 46 + 23 23
haploid
haploid
fertilization 46 21

22. Meiosis - Formation of Gametes
Meiosis only occurs during the production of gametes.
After fertilization, the diploid zygote divides by mitosis producing a multicellular, diploid organism.

23. Meiosis Meiosis reduces the chromosome number from diploid to haploid.
Occurs in two divisions, called meiosis I and meiosis II.
Divisions result in 4 daughter cells, each with half the number of chromosomes as the parent. (Haploid = n)
Meiosis 1 separates the homologous chromosomes (2 copies of each chromosome-1 from mom & 1 from dad) and Meiosis 2 separates sister chromatids.

24. Karyotype of a Female
Homologous chromosomes

25. Two Meiotic Divisions

26. Meiosis I

27. Meiosis II

28. Comparing Mitosis and Meiosis

29. Formation of Sperm vs. Formation of Eggs
4 haploid gametes … 4 sperm
Process = Spermatogenesis
4 haploid gametes …
1 Ovum (egg) & 3 Polar Bodies
Process = Oogenesis