chapter 8. cells must divide for growth repair cells cannot just continue to grow larger for two...
TRANSCRIPT
![Page 1: Chapter 8. Cells must divide for Growth Repair Cells cannot just continue to grow larger for two reasons: Exchanging materials The surface area of the](https://reader037.vdocuments.us/reader037/viewer/2022110210/56649e765503460f94b77adb/html5/thumbnails/1.jpg)
Chapter 8
![Page 2: Chapter 8. Cells must divide for Growth Repair Cells cannot just continue to grow larger for two reasons: Exchanging materials The surface area of the](https://reader037.vdocuments.us/reader037/viewer/2022110210/56649e765503460f94b77adb/html5/thumbnails/2.jpg)
Cells must divide forGrowthRepair
![Page 3: Chapter 8. Cells must divide for Growth Repair Cells cannot just continue to grow larger for two reasons: Exchanging materials The surface area of the](https://reader037.vdocuments.us/reader037/viewer/2022110210/56649e765503460f94b77adb/html5/thumbnails/3.jpg)
Cells cannot just continue to grow larger for two reasons:Exchanging materials
The surface area of the cell membrane must be large enough to support the volume of the cell.
Otherwise, the cell struggles keeping up with the exchange rate of food, oxygen and water across the membrane.
Information overloadToo many demands on the DNA to get its
information where it is needed.
![Page 4: Chapter 8. Cells must divide for Growth Repair Cells cannot just continue to grow larger for two reasons: Exchanging materials The surface area of the](https://reader037.vdocuments.us/reader037/viewer/2022110210/56649e765503460f94b77adb/html5/thumbnails/4.jpg)
Mitosis-The process by which a cell divides, forming
two “daughter” cellsThese daughter cells are identical to the
parent cell
![Page 5: Chapter 8. Cells must divide for Growth Repair Cells cannot just continue to grow larger for two reasons: Exchanging materials The surface area of the](https://reader037.vdocuments.us/reader037/viewer/2022110210/56649e765503460f94b77adb/html5/thumbnails/5.jpg)
Which cells ?Eukaryotic somatic (body) cells undergo
mitosisProkaryotic cells go through a process called
binary fission
![Page 6: Chapter 8. Cells must divide for Growth Repair Cells cannot just continue to grow larger for two reasons: Exchanging materials The surface area of the](https://reader037.vdocuments.us/reader037/viewer/2022110210/56649e765503460f94b77adb/html5/thumbnails/6.jpg)
ChromosomesMade up of DNA wrapped tightly around
histone proteinsDNA + histones = chromatin fiber and looks
like “beads on a string”During mitosis chromatin condenses and
coils to form chromosomes
![Page 7: Chapter 8. Cells must divide for Growth Repair Cells cannot just continue to grow larger for two reasons: Exchanging materials The surface area of the](https://reader037.vdocuments.us/reader037/viewer/2022110210/56649e765503460f94b77adb/html5/thumbnails/7.jpg)
Chromosome:Sister chromatids- Each side of a duplicated
chromosomeCentromere- Center of a chromosome, holds
sister chromatids together
![Page 8: Chapter 8. Cells must divide for Growth Repair Cells cannot just continue to grow larger for two reasons: Exchanging materials The surface area of the](https://reader037.vdocuments.us/reader037/viewer/2022110210/56649e765503460f94b77adb/html5/thumbnails/8.jpg)
Chromosome number varies for each speciesHumans= 46 Cat= 38Fruit fly= 8
![Page 9: Chapter 8. Cells must divide for Growth Repair Cells cannot just continue to grow larger for two reasons: Exchanging materials The surface area of the](https://reader037.vdocuments.us/reader037/viewer/2022110210/56649e765503460f94b77adb/html5/thumbnails/9.jpg)
The cell cycleMitosis is part of the cell’s life cycleThis cycle includes the following stages:
InterphaseMitosisCytokinesis
![Page 10: Chapter 8. Cells must divide for Growth Repair Cells cannot just continue to grow larger for two reasons: Exchanging materials The surface area of the](https://reader037.vdocuments.us/reader037/viewer/2022110210/56649e765503460f94b77adb/html5/thumbnails/10.jpg)
Interphase The longest phase of the cell cycleThe cell prepares to divide3 phases, or checkpoints, in Interphase
![Page 11: Chapter 8. Cells must divide for Growth Repair Cells cannot just continue to grow larger for two reasons: Exchanging materials The surface area of the](https://reader037.vdocuments.us/reader037/viewer/2022110210/56649e765503460f94b77adb/html5/thumbnails/11.jpg)
Phases of InterphaseG1 - intense cell growth, cells contents
duplicatedS - DNA is replicated (copied)G2 - more growth and final preparation for cell
divisionG0- cell enters this phase when something is
wrong and it either can’t or won’t divide. Ex: unstable environment, DNA was copied incorrectly, more cells not needed at that time
![Page 12: Chapter 8. Cells must divide for Growth Repair Cells cannot just continue to grow larger for two reasons: Exchanging materials The surface area of the](https://reader037.vdocuments.us/reader037/viewer/2022110210/56649e765503460f94b77adb/html5/thumbnails/12.jpg)
The Cell Cycle
![Page 13: Chapter 8. Cells must divide for Growth Repair Cells cannot just continue to grow larger for two reasons: Exchanging materials The surface area of the](https://reader037.vdocuments.us/reader037/viewer/2022110210/56649e765503460f94b77adb/html5/thumbnails/13.jpg)
After a cell goes through all the checkpoints, it is ready to divide!
The Mitotic phase of the cell cycle includes
ProphaseMetaphaseAnaphaseTelophase
![Page 14: Chapter 8. Cells must divide for Growth Repair Cells cannot just continue to grow larger for two reasons: Exchanging materials The surface area of the](https://reader037.vdocuments.us/reader037/viewer/2022110210/56649e765503460f94b77adb/html5/thumbnails/14.jpg)
ProphaseNuclear envelope disappearsChromatin condensesChromosomes are first visibleCentrioles split and move to opposite sides of
the cell
![Page 15: Chapter 8. Cells must divide for Growth Repair Cells cannot just continue to grow larger for two reasons: Exchanging materials The surface area of the](https://reader037.vdocuments.us/reader037/viewer/2022110210/56649e765503460f94b77adb/html5/thumbnails/15.jpg)
Prophase
![Page 16: Chapter 8. Cells must divide for Growth Repair Cells cannot just continue to grow larger for two reasons: Exchanging materials The surface area of the](https://reader037.vdocuments.us/reader037/viewer/2022110210/56649e765503460f94b77adb/html5/thumbnails/16.jpg)
Prophase
![Page 17: Chapter 8. Cells must divide for Growth Repair Cells cannot just continue to grow larger for two reasons: Exchanging materials The surface area of the](https://reader037.vdocuments.us/reader037/viewer/2022110210/56649e765503460f94b77adb/html5/thumbnails/17.jpg)
MetaphaseChromosomes line up in the middle of the
cell (equator)
Spindle fibers connect to chromosomes at the centromere
Metaphase = Middle
![Page 18: Chapter 8. Cells must divide for Growth Repair Cells cannot just continue to grow larger for two reasons: Exchanging materials The surface area of the](https://reader037.vdocuments.us/reader037/viewer/2022110210/56649e765503460f94b77adb/html5/thumbnails/18.jpg)
Metaphase
![Page 19: Chapter 8. Cells must divide for Growth Repair Cells cannot just continue to grow larger for two reasons: Exchanging materials The surface area of the](https://reader037.vdocuments.us/reader037/viewer/2022110210/56649e765503460f94b77adb/html5/thumbnails/19.jpg)
Metaphase (plant cell)
![Page 20: Chapter 8. Cells must divide for Growth Repair Cells cannot just continue to grow larger for two reasons: Exchanging materials The surface area of the](https://reader037.vdocuments.us/reader037/viewer/2022110210/56649e765503460f94b77adb/html5/thumbnails/20.jpg)
AnaphaseSister chromatids pulled apart to opposite
sides Spindle fibers shortenAnaphase = Away, or Apart
![Page 21: Chapter 8. Cells must divide for Growth Repair Cells cannot just continue to grow larger for two reasons: Exchanging materials The surface area of the](https://reader037.vdocuments.us/reader037/viewer/2022110210/56649e765503460f94b77adb/html5/thumbnails/21.jpg)
Anaphase
![Page 22: Chapter 8. Cells must divide for Growth Repair Cells cannot just continue to grow larger for two reasons: Exchanging materials The surface area of the](https://reader037.vdocuments.us/reader037/viewer/2022110210/56649e765503460f94b77adb/html5/thumbnails/22.jpg)
Anaphase
![Page 23: Chapter 8. Cells must divide for Growth Repair Cells cannot just continue to grow larger for two reasons: Exchanging materials The surface area of the](https://reader037.vdocuments.us/reader037/viewer/2022110210/56649e765503460f94b77adb/html5/thumbnails/23.jpg)
TelophaseTwo sets of genetic information on either side
of the cellNuclear envelope reforms around each setChromosomes no longer visible (unravel into
chromatin again)
![Page 24: Chapter 8. Cells must divide for Growth Repair Cells cannot just continue to grow larger for two reasons: Exchanging materials The surface area of the](https://reader037.vdocuments.us/reader037/viewer/2022110210/56649e765503460f94b77adb/html5/thumbnails/24.jpg)
Telophase
![Page 25: Chapter 8. Cells must divide for Growth Repair Cells cannot just continue to grow larger for two reasons: Exchanging materials The surface area of the](https://reader037.vdocuments.us/reader037/viewer/2022110210/56649e765503460f94b77adb/html5/thumbnails/25.jpg)
After mitosis is complete, the cell has one thing left to do- split! (cytokinesis)
![Page 26: Chapter 8. Cells must divide for Growth Repair Cells cannot just continue to grow larger for two reasons: Exchanging materials The surface area of the](https://reader037.vdocuments.us/reader037/viewer/2022110210/56649e765503460f94b77adb/html5/thumbnails/26.jpg)
CytokinesisSplitting of the cytoplasmForms two new distinct “daughter” cells Two cells are genetically identicalIn animals- Cell membrane “pinches off”In plants- Cell plate forms
![Page 27: Chapter 8. Cells must divide for Growth Repair Cells cannot just continue to grow larger for two reasons: Exchanging materials The surface area of the](https://reader037.vdocuments.us/reader037/viewer/2022110210/56649e765503460f94b77adb/html5/thumbnails/27.jpg)
CytokinesisIn animals: Cell membrane “pinches off”
In plants: Cell plate forms
![Page 28: Chapter 8. Cells must divide for Growth Repair Cells cannot just continue to grow larger for two reasons: Exchanging materials The surface area of the](https://reader037.vdocuments.us/reader037/viewer/2022110210/56649e765503460f94b77adb/html5/thumbnails/28.jpg)
Video linkshttp://www.youtube.com/watch?v=VlN7K1-
9QB0
http://www.youtube.com/watch?v=nPG6480RQo0&feature=related
![Page 29: Chapter 8. Cells must divide for Growth Repair Cells cannot just continue to grow larger for two reasons: Exchanging materials The surface area of the](https://reader037.vdocuments.us/reader037/viewer/2022110210/56649e765503460f94b77adb/html5/thumbnails/29.jpg)
![Page 30: Chapter 8. Cells must divide for Growth Repair Cells cannot just continue to grow larger for two reasons: Exchanging materials The surface area of the](https://reader037.vdocuments.us/reader037/viewer/2022110210/56649e765503460f94b77adb/html5/thumbnails/30.jpg)
THE END