1. Viewing Cells 2.2

2. I. Microscopes Put magnification to work… 1) Go out side and grab a leaf or blade of grass. 2) Make a wet-mount slide 3)Observe and draw a picture (label the cell wall, chloroplasts, vacoule and nucleus)

3. I. Microscopes A.1 st Microscope 1. Antonie van Leeuwenhoek 2. Late 1500’s 3. Noticed that 2 lenses from reading glasses made an image bigger. 4. Magnified image 270X

4. I. Microscopes B. Compound Microscope 1. Uses 2 lenses (simple only uses 1) 1 lens in the eyepiece X 1 objective lens ---------------------------- Total Magnification

5. I. Microscopes 2. Eyepiece = 10 X Objective Lens = 40 ------------------------ Magnification = 400X 3. Compound microscopes can magnify up to 2000X

6. I. Microscopes C. Electron Microscopes 1. Uses a beam of electrons instead of a light beam a. Images are viewed in a vacuum so they cannot be alive. 2. Can magnify up to 1,000,000X

7. I. Microscopes 3. Types of Electron Microscopes a. Scanning Electron Microscope (SEM) 1)Makes a 3-D image of the cell’s surface.

8. I. Microscopes b. Transmission Electron Microscope (TEM) 1)Makes a 2-D image of the structures inside the cell

9. I. Microscopes c. Scanning Tunneling Microscope (STM) 1) Shows the atoms on the surface of a cell 2) VERY POWERFULL! 3) Uses computer generated graphics

10. II. Cell Theory A.All organisms are made up of 1 or more cells 1. Hooke first noticed cells 1. Schleiden noticed this in plants 2. Schwann noticed this in animal cells B. The cell is the basic unit of organization in organisms

11. II. Cell Theory C.All Cells come from pre- existing cells 1. Virchow noticed that cells divide from other cells to reproduce

12. III. Prokaryote vs. Eukaryote A.Prokaryote (“Pro” means NO) 1. No nucleus 2. No nucleus 3. No membrane-bound organelles (Not very organized) 4. No more than 1 cell (Single- celled organisms)

13. III. Prokaryote vs. Eukaryote B. Eukaryote 1. Has a nucleus 2. Has membrane bound organelles 3. More organized 4. Single or multi-celled organisms

14. RECAP -Who is the inventor of the microscope -What kind of microscope uses 2 lenses to magnify -How is an electron microscope different from a compound microscope

15. RECAP -What are the 3 parts of the cell theory? -Who named cells? Why did he name them cells? -What is the difference between a prokaryote and a eukaryote?