Chapter 10 - Mitosis and Cytokinesis Warm Up – 11/20 List the differences between Asexual and Sexual Reproduction. Name two types of asexual reproduction. What are the three parts of interphase? (List them in order) Provide what happens in each part of interphase.

Chapter 10 - Mitosis and Cytokinesis Warm –Up 11/20 What is the diagram on the right? Compare the terms chromatid and chromosome! Chromatid Answer: Duplicated Chromosome Answer: The are the essentially the same. Both are one half of the duplicated chromosome. After the duplicated chromosome splits - chromatids are then called a chromosomes.

13.1 Ecologists Study Relationships What are Chromosomes? The Cell Cycle Vocabulary – 1 Chromosome - an organized structure of DNA and protein that is found in cells. It is a single piece of coiled DNA containing many genes.

Chapter 10 - Mitosis and Cytokinesis A complete set of human chromosomes (Each band is a gene) The Cell Cycle Vocabulary - 2

Chapter 10 - Mitosis and Cytokinesis Chromosomes vs Sister Chromatids vs Chromatid Sister chromatids are held together at the centromere. Identical chromosomes (carry the same genes) When attached to each other one half of a duplicated chromosome is a chromatid. When sister chromatids separate they are called chromosomes Pair of sister chromatids chromatid centromere 9 The Cell Cycle Vocabulary – Page 2

Chapter 10 - Mitosis and Cytokinesis DNA double helix DNA and histones Chromatin Supercoiled DNA Sister Chromatids 9 The Cell Cycle Vocabulary

Chapter 10 - Mitosis and Cytokinesis The cell cycle in body cells includes Interphase and Mitosis * The cell grows and replicates its DNA during Interphase. * The cells nucleus divides during mitosis * Cytokinesis is the division of the cytoplasm this occurs after mitosis 9 The Cell Cycle in Somatic Cells (body cells) – Page 5

Chapter 10 - Mitosis and Cytokinesis Interphase: includes G1, S, and G2 phases –Gap 1 (G 1 ): cell growth and normal functions –Synthesis (S): copies DNA, DNA replication –Gap 2 (G 2 ): additional growth The Cell Cycle in Somatic Cells – Page 7

Chapter 10 - Mitosis and Cytokinesis chromatin Interphase: prepares the cell for mitosis The cell grows (G1) DNA Reproduction: The DNA is duplicated. (S) Interphase prepares the cell to divide. (G2) Nuclear envelope Interphase 9 The Cell Cycle Interphase – Page 6 - Chromatin: thread-like genetic material in the nucleus

Chapter 10 - Mitosis and Cytokinesis Mitosis begins : Mitosis (M): division of the somatic cell’s nucleus Cytokinesis: division of the somatic cell’s cytoplasm Includes P.M.A.T. Prophase Metaphase Anaphase Telophase The Cell Cycle Somatic Cells Produces two genetically identical daughter cells.

Chapter 10 - Mitosis and Cytokinesis –Chromatin is condensed and duplicated chromosomes are visible –Spindle fibers form –Nuclear envelope disappears Nuclear Envelope Sister Chromatids Spindles Forming 9 Mitosis Begins: Division of the Nucleus – Page 8 & 9 Prophase: First step of mitosis

Chapter 10 - Mitosis and Cytokinesis Metaphase: second step of mitosis –Sister chromatids line up in the middle of the cell. –Spindle fibers attach to sister chromatids Sister Chromatids Centromere 9 The Cell Cycle Mitosis – Page 10 & 11

Chapter 10 - Mitosis and Cytokinesis Anaphase: third step of mitosis –Sister chromatids move apart and are now called chromosomes –Spindles pull identical chromosomes to opposite sides of the cell. Chromosome Centromere Spindle Fiber 9 The Cell Cycle Mitosis – Page 12 & 13

Chapter 10 - Mitosis and Cytokinesis Connecting Question During anaphase identical chromosomes are pulled to opposite ends of the cell. Hypothesize: 1. Where did the two identical copies come from? Answer 1. The Interphase – Synthesis (S) – Why? - This is when the cell duplicates its genetic information to get ready for mitosis.

Chapter 10 - Mitosis and Cytokinesis Telophase: fourth step of mitosis –The two new nuclei form. –Chromosomes begin to uncoil and form chromatin. –Nuclear envelope reappears. Nuclear Envelope Identical Chromosomes 9 The Cell Cycle Mitosis – Page 15

Chapter 10 - Mitosis and Cytokinesis Cytokinesis: the cells cytoplasm splits after mitosis –Parent cell splits into two –2 identical daughter cells form –In animal cells, the membrane pinches closed. –In plant cells, a cell plate forms. nucleus with chromatin 9 Two Identical Daughter Cells Form (Cytokinesis) The Cell Cycle Cytokinesis – Page 16

Chapter 10 - Mitosis and Cytokinesis Closing Questions 1. Analyze the cell cycle in order to determine: A. In what phase(s) could you find individual chromosomes in the cell. B. After which phase(s) would you find sister chromatids (duplicated chromosomes) in the cell. 2. Hypothesize why it is important for the sister chromatids to remain attached at the centromere until anaphase.

Chapter 10 - Mitosis and Cytokinesis Controls on Cell Division How is the cell cycle regulated? The cell cycle is controlled by regulatory proteins both inside and outside the cell.

The controls on cell growth and division can be turned on and off. For example, when an injury such as a broken bone occurs, cells are stimulated to divide rapidly and start the healing process. The rate of cell division slows when the healing process nears completion.

Chapter 10 - Mitosis and Cytokinesis The Discovery of Cyclins Cyclins - are a family of proteins that regulate the timing of the cell cycle in eukaryotic cells.

Chapter 10 - Mitosis and Cytokinesis Apoptosis Apoptosis is a process of programmed cell death. Apoptosis plays a role in development by shaping the structure of tissues and organs in plants and animals. For example, the foot of a mouse is shaped the way it is partly because the toes undergo apoptosis during tissue development.

Chapter 10 - Mitosis and Cytokinesis Cancer Do you know anyone (or of anyone) who has been diagnosed with cancer? If so, what cancer did they have? What type of cancers do you think are most prevalent?

Most Common Types of Cancer (National Cancer Institute) Type of CancerNew Cases AnnuallyDeaths Breast (Female – Male)235,03040,430 Prostate233,00029,480 Lung (Including Bronchus)224,210159,260 Colon and Rectal (Combined)136,83050,310 Melanoma76,1009,710 Bladder74,69015,580 Non-Hodgkin Lymphoma70,80018,990 Kidney (Renal Cell and Renal Pelvis) Cancer63,92013,860 Thyroid62,9801,890 Endometrial52,6308,590 Leukemia (All Types)52,38024,090 Pancreatic46,42039,590

Most Common Types of Cancer (National Cancer Institute) Type of CancerNew Cases AnnuallyDeathsMortality Rate Pancreatic46,42039,590 85% Lung (Including Bronchus)224,210159,260 71% Leukemia (All Types)52,38024,090 46% Colon and Rectal (Combined)136,83050,310 37% Non-Hodgkin Lymphoma70,80018,990 27% Kidney (Renal Cell and Renal Pelvis)63,92013,860 22% Bladder74,69015,580 21% Breast (Female – Male)235,03040,430 17% Endometrial52,6308,590 16% Melanoma76,1009,710 13% Prostate233,00029,480 13% Thyroid62,9801,890 3%

Chapter 10 - Mitosis and Cytokinesis Common Cancers Melanoma (deadly type of skin cancer) Leukemia (cancer of the circulatory system – blood) Lung Cancer Colon Cancer Breast Cancer Bladder Cancer

Chapter 10 - Mitosis and Cytokinesis Cancer… Mitosis Out of Control!!!! out-of-control cell production Cancer results from out-of-control cell production. tumors Abnormal masses of cells are called tumors.

Chapter 10 - Mitosis and Cytokinesis Two Types of Tumors Tumors can either be: Benign – abnormal mass of cells. It does not spread to surrounding healthy tissue. Malignant – mass of cells resulting from the reproduction of cancer cells. It invades and destroys surrounding healthy tissue and can spread to other parts of the body. Brain Tumor (MRI)

Chapter 10 - Mitosis and Cytokinesis Metastasis When cancer cells break off tumors and travel (spread) to other places in the body, the cancer is said to have metastasized.

Chapter 10 - Mitosis and Cytokinesis Cancer Treatment Surgery Radiation Therapy Chemotherapy Unwanted Side Effects – nausea, damage to organs, sterility, hair loss, etc.