2. 7.1 The Discovery of Cells Cell Theory 1.All organisms are composed of one or more cells. 2.The cell is the basic unit of organisms. 3.All cells come from preexisting cells. content.answers.com/.../ 300px-Hooke's_cork.png

3. 7.1 The Discovery of Cells All cells come from one cell…they just keep dividing All cells contain all the genetic info. or DNA Some cells have special functions and use only a small part of the DNA www.csa.com/.../stemcell/images/pluri.jpg

4. 7.1 The Discovery of Cells Types of Cells –Prokaryotic No membrane bound organelles No nucleus Most unicellular organisms ww.phschool.com/.../ images/cells/allcell.jpg

5. 7.1 The Discovery of Cells –Eukaryotic Membrane bound organelles Nucleus Most multicellular (except ameobas, yeast and some algae) Much larger (see pg 174)

6. Animal vs. Plant Cell Note the differences!

7. CELLS ProkaryoticEukaryotic Animal cellPlant Cell

8. Cell Wall Found in plant cells Located outside the Plasma membrane Function: protection and support Made of cellulose

9. 7.2 The Plasma Membrane Plasma Membrane: –Flexible boundary between cells & environment –Selectively permeable: ___ –Phospholipid Bilayer –Cholesterol, Protein nai.arc.nasa.gov/team/ images/2006/ciw/1829/1.jpg www.biology.arizona.edu/.../ graphics/bilayer.giff fig.cox.miami.edu/.../ 150/memb/fluidmosaic.jpg

10. 7.2 The Plasma Membrane Fluid Mosaic Model http://www.bio.davidson.edu/people/macampbell/111/memb-swf/membranes.swf fig.cox.miami.edu/.../ 150/memb/fluidmosaic.jpg

11. 7.2 The Plasma Membrane academic.brooklyn.cuny.edu/biology/bio4fv/pag...

12. Nucleus Manages and controls all cell functions Holds genetic information Nucleolus is found there –Makes ribosomes www.palaeos.com/.../Lists/Images/nucleolus.jpg iweb.tntech.edu/mcaprio/normalonionskin.jpg