Chapter 10 cell Reproduction

1. Chapter 10cell Reproduction • Mitosis – cell reproduction A. Body Growth and Repair 1. Mitosis is cell reproduction in which two identical cells are made fromeach other. 2. Body Cells are cells that make up most of the body

2. II. An Introduction to Mitosishttp://www.cellsalive.com/mitosis.htm II. An Introduction to Mitosis • How does mitosis work? You begin with one cell and you end up with two identical cells. This process can take up to several hours. B. What cell parts are used in mitosis The cell parts used during mitosis are the cytoplasm, nuclear membrane, nucleus, chromosomes and centrioles

3. Cell Size • Information overload • If a cell grows too large, the DNA cannot meet the needs of the cell • Affects how well a cell can move materials in and out of the cell through the cell membrane.

4. Ratio to surface area • The size of the cell surface does not grow as fast as it’s volume. • The cell as a living thing can not be as effective • When the cell grows to capacity, then it needs to go through cell division.

5. Cell Division – is the process when cells divide into two cells. - Mitosis – Eukaryotes - Binary fission - Prokaryotes • Asexual reproduction – reproduction by a single parent • Sexual Reproduction - reproduction by two parents

6. Chromosomes 1. Chromosomes package molecules of DNA. In a eukaryote cell, Chromosomes are packaged into the nucleus of the cell. Prokaryotes, the chromosomes are not packaged into the nucleus. 2. Chromosomes are sometimes 1000 times larger then the cell and are wound and folded into the cell very carefully.

7. The Cell cycle: 1. Prokaryotes cell cycle would be binary fission a. DNA duplicates b. Cell membrane indents c. Cell divides into two

8. http://www.johnkyrk.com/mitosis.html 2. Eukaryote cell cycle. a. begins with Interphase, which include G1, S, and G2 b. M Phase: Cell Division – the M in M phase stands for mitosis, which is the first stage of M Phase. The second phase of the M phase is Cytokinesis.

9. Fill the correct phases in the diagram. • M • S • G1 • G2

10. 3. Steps of Mitosis: 1. Prophase – chromosomes replicate and then duplicate becoming sister chromatids. The sister chromatids join in the center which is called the centromere. The nuclear membrane breaks down, and spindle fibers begin to form. 2. Metaphase – the sister chromatids line up in the center of the cell 3. Anaphase – chromosomes split and sister chromatids separates. A complete set of chromosomes move to each end of the cell.

11. 4. Telophase – the chromosomes spread out within each cell in a tangle of chromatin. The nuclear membrane reforms around each group of chromosomes. Spindle fibers begin to break down. 5 Cytokinesis in animal cells – cell membrane is pulled toward the center of cell. Cytoplasm is pinched apart into two identical cells Cytokinesis in plant cells – a plant cell is not flexible enough to pinch in two, as a result a cell plate forms between the two cells.

12. Regulator proteins: • External regulators – Proteins that respond to events outside the cell which will speed up or slow down the process of cell division. (injury or broken bone) • Internal regulators – proteins that respond to events inside the cell. (These proteins make sure the DNA duplication is complete before the cell divides.)

13. 3. Apoptosis is a protein that tells the cell to go through a series of steps that lead to cell death. Cancer: 1. Cancerous Tumors – cancer cells form into a mass 2. What causes cancer – Damage to a cells DNA 3. Treatment for cancer – surgery, radiation, chemo therapy

15. Cell Differentiation: 1. Embryo – one cell from a single fertilized egg. - as the embryo grows, cells differentiate 2. Differentiation – a cell that has become different from the original cell produced. 3. Differentiated cells perform different jobs.

16. Stem Cell development: 1. Totipotent cells are cells that can develop into any type of cell. 2. Pluripotent – are cells that can develop into all body cells except the tissues that make up the tissue that surround the embryo. 3. Stem Cells – specialized cells that can develop from unspecialized cells.

17. 4. Multipotentcells – Are adult stem cells that can develop into many but not all types of differentiated cells. Benefits of Stem cell research: 1. Hope to improve human health - fix cells that have been damaged example: fix heart attack damage

18. Ethical issues: 1. Scientists have to destroy an embryo in order to produce stem cells.