1. Microscopes  How can we observe cells?

2. What technology allows biologists to study microscopic life?  A. Compound Light Microscope 1.Has two lenses – ocular (eyepiece) and objective 2.In order to be viewed, specimen must be thin (so the light may shine through the specimen) and placed on a slide. 3.Specimen may be stained to better see structures

3. Fill It In … Label the ocular lens and the objective lens:

4. What technology allows biologists to study microscopic life?  B. Electron Microscope 1.Uses electrons to produce an image 2.Types: a.Scanning Electron Microscope (SEM) i.Electrons scan the surface of a specimen ii.Produces a ii.Produces a 3-D image

5. What technology allows biologists to study microscopic life?  B. Electron Microscope a.Transmission Electron Microscope (TEM) i.Designed to look at structures inside a cell ii.Capable of greatest magnification

7. What technology allows biologists to study microscopic life? C. Limitations of microscopes 1.Magnification is limited by the strength of the lens. a.Calculating magnification: Ocular lens x objective lens = total magnification b.Example: Ocular (10x) x objective (40x) = 400x 2.As magnification increases resolution/(sharpness) decreases.

8. Check Yourself! 1.Why must specimens be thin for a compound light microscope? 2.Which microscope provides the highest possible magnification? 3.If the ocular lens is 10x and the objective lens is 10x then the total magnification is? 4.As magnification increases, resolution _______________ 1.Why must specimens be thin for a compound light microscope? 2.Which microscope provides the highest possible magnification? 3.If the ocular lens is 10x and the objective lens is 10x then the total magnification is? 4.As magnification increases, resolution _______________

9. Check Yourself! 1.Why must specimens be thin for a compound light microscope? TO ALLOW LIGHT TO PASS THROUGH THE SPECIMEN 2.Which microscope provides the highest possible magnification? 3.If the ocular lens is 10x and the objective lens is 10x then the total magnification is? 4.As magnification increases, resolution _______________ 1.Why must specimens be thin for a compound light microscope? TO ALLOW LIGHT TO PASS THROUGH THE SPECIMEN 2.Which microscope provides the highest possible magnification? 3.If the ocular lens is 10x and the objective lens is 10x then the total magnification is? 4.As magnification increases, resolution _______________

10. Check Yourself! 1.Why must specimens be thin for a compound light microscope? TO ALLOW LIGHT TO PASS THROUGH THE SPECIMEN 2.Which microscope provides the highest possible magnification? TEM (TRANSMISSION ELECTRON) 3.If the ocular lens is 10x and the objective lens is 10x then the total magnification is? 4.As magnification increases, resolution _______________ 1.Why must specimens be thin for a compound light microscope? TO ALLOW LIGHT TO PASS THROUGH THE SPECIMEN 2.Which microscope provides the highest possible magnification? TEM (TRANSMISSION ELECTRON) 3.If the ocular lens is 10x and the objective lens is 10x then the total magnification is? 4.As magnification increases, resolution _______________

11. Check Yourself! 1.Why must specimens be thin for a compound light microscope? TO ALLOW LIGHT TO PASS THROUGH THE SPECIMEN 2.Which microscope provides the highest possible magnification? TEM (TRANSMISSION ELECTRON) 3.If the ocular lens is 10x and the objective lens is 10x then the total magnification is? 10 X 10 = 100X 4.As magnification increases, resolution _______________ 1.Why must specimens be thin for a compound light microscope? TO ALLOW LIGHT TO PASS THROUGH THE SPECIMEN 2.Which microscope provides the highest possible magnification? TEM (TRANSMISSION ELECTRON) 3.If the ocular lens is 10x and the objective lens is 10x then the total magnification is? 10 X 10 = 100X 4.As magnification increases, resolution _______________

12. Check Yourself! 1.Why must specimens be thin for a compound light microscope? TO ALLOW LIGHT TO PASS THROUGH THE SPECIMEN 2.Which microscope provides the highest possible magnification? TEM (TRANSMISSION ELECTRON) 3.If the ocular lens is 10x and the objective lens is 10x then the total magnification is? 10 X 10 = 100X 4.As magnification increases, resolution _DECREASES_ 1.Why must specimens be thin for a compound light microscope? TO ALLOW LIGHT TO PASS THROUGH THE SPECIMEN 2.Which microscope provides the highest possible magnification? TEM (TRANSMISSION ELECTRON) 3.If the ocular lens is 10x and the objective lens is 10x then the total magnification is? 10 X 10 = 100X 4.As magnification increases, resolution _DECREASES_

13. Cheek Cells!