1. CELL REPRODUCTION
THE CELL CYCLE AND MITOSIS

2. Lesson Objectives—Cell Cycle
Describe the properties of cell division in prokaryotes.
Describe cell division in eukaryotes. Explain the main differences between cell division in prokaryotic and eukaryotic cells.
Describe the basic properties of chromosomes.
Describe the key steps in the cell cycle.
Identify and describe the main processes in mitosis.
Describe how the cell cycle is controlled and define cancer.

3. Functions of Cell Division
20 µm
100 µm
200 µm
(a) Reproduction. An amoeba, a single-celled eukaryote, is dividing into two cells. Each new cell will be an individual organism (LM).
(b) Growth and development This micrograph shows a sand dollar embryo shortly after the fertilized egg divided, forming two cells (LM).
(c) Tissue renewal. These dividing bone marrow cells (arrow) will give rise to new blood cells (LM).

4. CELL REPRODUCTION
Cell Division: process by which a cell divides to form two new cells (daughter cells)
Three types of cell division, or cell reproduction
Prokaryotes (bacteria)
Binary fission divides forming two new identical cells
Eukaryotes
Mitosis
Cell or organism growth
Replacement or repair of damaged cells
Meiosis
formation of sex cells, or gametes

5. EUKARYOTIC CELL DIVISION
DNA found on chromosomes located in nucleus of cell
Cell cycle continuous process
Cells grow
DNA replicated
Organelles duplicated
Divide to form daughter cells
2 Main steps:
1: Mitosis (4 steps—Prophase, Metaphase, Anaphase, Telophase)
Nucleus divides
2: Cytokinesis—Cytoplasm divide, forming 2 cells
Each new daughter cell is genetically identical to parent cell

6. Mitosis = nuclear division
Mitosis is followed by cytokinesis (cell division)
The steps of mitosis ensure that each new cell has the exact same number of chromosomes as the original

7. Structure of Chromosomes
Chromosomes are composed of a complex of DNA and protein called chromatin that condenses during cell division

8. MITOSIS
Process that divides cell nucleus to produce two new nuclei each with a complete set of chromosomes
Continuous process
Four phases (PMAT)
Prophase
Metaphase
Anaphase
Telophase

9. PMAT (1)Prophase (2)Metaphase (3)Anaphase (4)Telophase Interphase 1 2
Cytokinesis

10. 1. chromosomes visible (sister chromatids)
2. centrioles migrate to the poles (only in animals)
3. nuclear membrane disappears
4. spindle forms

11. chromosomes line up on the equator of the cell
spindles attach to centromeres
Equator

12. sister chromatids separate
centromeres divide
sister chromatids move to opposite poles

13. 1. chromosomes uncoil • now chromatin
2. nuclear membranes reform
3. spindle disappears

14. Occurs at end of Mitosis
--division of the cytoplasm to form 2 new daughter cells
--organelles are divided
-Daughter cells are genetically identical
Cells return to interphase

16. Mitotic Division of an Animal Cell
INTERPHASE
PROPHASE
Centrosomes (with centriole pairs)
Chromatin (duplicated)
Centromere

17. Mitotic Division of an Animal Cell
METAPHASE
ANAPHASE
TELOPHASE AND CYTOKINESIS
Nuclear envelope forming
Daughter chromosomes

18. Name the phases starting at the top.
Mitosis
Name the phases starting at the top.

19. 2.Name the phase
3.Identify X
4.Identify Y

20. 5. Name the phase

21. 6. Name the phase