1 / 29

Cell Growth and Division

Cell Growth and Division. Chapter 10. 10-1 Cell Growth. Limits to cell growth The bigger a cell is, the more demands the cell places on its DNA. The cell has trouble moving enough nutrients and wastes across the cell membrane. 10-1 Cell Growth. DNA “overload”

lael
Download Presentation

Cell Growth and Division

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Cell Growth and Division Chapter 10

  2. 10-1 Cell Growth • Limits to cell growth • The bigger a cell is, the more demands the cell places on its DNA. • The cell has trouble moving enough nutrients and wastes across the cell membrane

  3. 10-1 Cell Growth • DNA “overload” • DNA – provides information that controls the cell’s funtions • Small cells have less need for that information than big cells • Big cells may need so much information that the single copy of DNA cannot provide it to all areas of the cell

  4. 10-1 Cell Growth • Exchanging materials • Surface area of a cell determines the amount of material exchanged • Oxygen, water, and food • Total area of the cell membrane • Volume of a cell determines how fast these materials are produced (waste) or used (food and oxygen)

  5. 10-1 Cell Growth • Ratio of surface area to volume • Surface area / volume • Surface area • Length X Width X Number of sides • units 2 • Volume • Length X Width X Height • units 3

  6. 10-1 Cell Growth • If the length of the cell doubles what happens to the ______? • Volume • Surface Area • Ratio SA / V • What does this do to the cell?

  7. 10-1 Cell Growth • Division of the cell • Cell division • The process by which a cell divides forming two new daughter cells • This occurs when the cell becomes too big • Before a cell divides, it replicates its DNA.

  8. 10-2 Cell Division • What do we call the chromosomes when they have replicated? • What is the structure that holds the replicated chromosomes together? • What is the longest phase of the cell cycle? • In what phase of the cell cycle does the cell do most of their growing? • What does the “S” stand for in the S-phase and what occurs during this phase?

  9. 10-2 Cell Division • Chromosomes • Carries the cells genetic information from one generation to the next. • Made of DNA and proteins • Each cell contains a specific number of chromosomes • Humans – 46 • Apes - 48 • Flies - 8 • Carrot – 18 • Dog - 78

  10. 10-2 Cell Division • Chromatids • One of two identical “sister” parts of a duplicated chromosome • Centromeres • Area where the chromatids of a chromosome are attached

  11. 10-2 Cell Division • The cell cycle • Interphase • Period of the cell cycle between cell divisions • Cell cycle • During the cell cycle, a cell grows, prepares for division, and divides to form two daughter cells, each of which then begins the cycle again

  12. 10-2 Cell Division • Events of the cell cycle • G1 phase • Cell growth • S phase • DNA replication • G2 phase • Preparation for mitosis • M phase • Cell division (mitosis and cytokinesis)

  13. 10-2 Cell Division • Mitosis • Division of the cell nucleus • Four phases (PMAT) • Prophase, metaphase, anaphase, and telophase

  14. 10-2 Cell Division • Prophase • 1st phase • Longest phase • Chromosomes become visible • Nuclear envelope dissolves • Centrioles separate • Spindles begin to form

  15. 10-2 Cell Division

  16. 10-2 Cell Division • Metaphase • Chromosomes line up across the center of the cell • Each chromosome is connected to a spindle fiber

  17. 10-2 Cell Division

  18. 10-2 Cell Division • Anaphase • Sister chromatids separate into individual chromosomes • Chromosomes move toward opposite poles

  19. 10-2 Cell Division

  20. 10-2 Cell Division • Telophase • Chromosomes gather at the poles and lose their shape • New nuclear envelopes surround each set of chromosomes

  21. 10-2 Cell Division

  22. 10-2 Cell Division • Cytokinesis • Division of the cytoplasm • Each daughter cell has an identical set of chromosomes

  23. 10-2 Cell Division

  24. 10-3 Regulating the Cell Cycle • What are some of the controls of cell division? • What are the substances that regulate the timing of the cell cycle? • What is it called when a cell experiences uncontrolled cell growth? • What are some causes of uncontrolled cell growth? • What is the importance of the p53 gene?

  25. 10-3 Regulating the Cell Cycle • Controls of cell division • Cell growth can be turned on or off • On • Injury • Off • Cells become crowded

  26. 10-3 Regulating the Cell Cycle • Cell cycle regulators • Something that tells the cell when it is time to divide, duplicate their chromosomes, or enter another phase • Cyclin • Protein that cause spindles to form • Regulate the timing of the cell cycle in eukaryotic cells

  27. 10-3 Regulating the Cell Cycle • Internal regulators • Proteins that respond to events inside the cell • Allow the cell to proceed only when certain processes have happened

  28. 10-3 Regulating the Cell Cycle • External regulators • Proteins that respond to events outside the cell • Direct the cell to speed up or slow down the cell cycle • Ex. Growth factor

  29. 10-3 Regulating the Cell Cycle • Uncontrolled cell growth • Cancer • Cancer cells do not respond to the signals that regulate the growth of most cells

More Related