Mitotic Cell Division Involves mitosis and cytokinesis Picture A. Mitosis -Replicated chromosomes separate B. Cytokinesis -After replicated chromosomes separate, the cytoplasm divides forming two cells

What are Chromosomes??

Rod-like structures in the cell’s nucleus that contain DNA… When a cell is not dividing, DNA is in long thin threads called… Only appear when cell is dividing Chromatin

Chromosome # is different for many organisms… Human = Fruit Fly = Onion = Goldfish= - Not number of chromosomes, but the information contained in them that determines complexity

Why does mitotic cell division take place? In multicellular organisms… 1. for growth 2. for tissue repair In simple organisms (ameba, paramecium, hydra)… 1. reproduce asexually

Interphase and Stages of Mitotic Cell Division - Interphase – Not a stage in mitosis 1. Prophase 2. Metaphase 3. Anaphase 4. Telophase -Cytokinesis

Overview of Mitotic Cell Division

1. Interphase (IPMAT) hrs DNA contained in threads of Chromatin. DNA in Chromatin replicates in s-stage. Chromosomes not formed yet. When chromosomes form in prophase, they will be doubled…

Picture Interphase

Doubled chromosomes visible. Each strand of doubled chromosomes is a chromatid. The chromatids are connected at a region called centromere Centrioles start to move to opposite poles. Spindle fibers (consist of a microtubule) form between centrioles. By end, nuclear membrane & nucleolus disappear. 2. Prophase (IPMAT)

Prophase Picture

3. Metaphase (IPMAT) Chromosomes attached to spindle fibers at centromere. Double stranded chromosomes line up in single file at equator.

Picture Metaphase

4. Anaphase (IPMAT) -Spindle fibers shorten and pull chromatids apart. -Single stranded chromosomes are moved to opposite poles.

Picture Anaphase

5. Telophase (IPMAT) -Division furrow forms -Single stranded chromosomes reach opposite poles. -Two new identical nuclei form. Division Furrow

Picture Telophase

6. Cytokinesis - At end of mitosis, cytoplasm divides forming 2 identical daughter cells.

Prophase

Metaphase

Anaphase

Telophase

When the cell is ready to divide it organizes it’s DNA into _______________________. 1.Nuclei 2.Chromosomes 3.Centromeres 4.Chromatids Why is it important to organize the DNA before division?

Name that Phase 1.Metaphase 2.Anaphase 3.Telophase 4.Cytokensis 5.Prophase Why is this phase important?

Name that Phase 1.Metaphase 2.Anaphase 3.Telophase 4.Cytokensis 5.Prophase Why is this phase important?

Name that Phase 1.Metaphase 2.Anaphase 3.Telophase 4.Cytokensis 5.Prophase Why is this phase important?

Name that Phase 1.Metaphase 2.Anaphase 3.Telophase 4.Cytokinesis 5.Prophase Why is this phase important?

Name that Phase 1.Metaphase 2.Anaphase 3.Telophase 4.Cytokensis 5.Prophase Why is this phase important?

Animal Cell vs. Plant Cell Mitosis

Basic process the same. No centrioles in plant cells. Cytokinesis in animal cells is by a Divison Furrow, in plant cells a Cell Plate of cellulose is formed- will become cell wall.

Cancer Cells have a built-in cycle that tells them how to grow, divide, and when to stop dividing Sometimes a cell mutates and its cycle doesn’t work as it should. Uncontrolled Cell DivisionThe cell doesn’t get the signal to stop dividing (Uncontrolled Cell Division)

DiagramCentrioles DiagramCentrioles