1. MICROSCOPES

2. Microscope Quiz Friday –Jan. 28 n Label parts of microscope n How to use (ex: use coarse knob to find object, adjust diaphragm for light) n Total Magnification (eyepiece X objective) n How to Measure (field diam. n number across) n Convert mm to µm (4 mm = 4000 µm)

3. Compound Light Microscope Parts

4. Compound Light n Uses two lenses –ocular –objective n To bend light

5. Resolving Power n Being able to tell two objects apart n Measure of “clarity”-how clear it is

6. Resolving Power n smallest separation between two object points that a given lens (or mirror) can still show as two distinct entities, not one n...

7. Pollen Under 1000X LM Over 1000 X SEM

8. MAGNIFICATION n Increase in the apparent size of an object n MULTIPLY THE OCULAR LENS x THE OBJECTIVE –OCULAR 10x –OBJECTIVE 40 x –WHAT IS THE TOTAL MAGNIFICATION? –400 x

9. How do they look different? n Leaf 4X n Leaf 10 X

10. ADVANTAGES of CLM: n CAN MAGNIFY UP TO 1000 x n CAN VIEW LIVING THINGS n Resolving power 200 nm or 0.2 µm

11. Disadvantages of LM n Objects must be thin or transparent so light can go through them n The image is inverted

12. Pictures of LM microorganisms Can be stained

13. Dissecting Light Microscope n Image is NOT inverted n Usually 40 X is the limit

14. Light-colored stage for dark specimens and dark-colored stage for light ones Dissecting Scope Viewing

15. Dissection Scope View of Insect Wing

16. ELECTRON MICROSCOPES n USE MAGNETS TO FOCUS A BEAM OF ELECTRONS –TEM (Transmission Electron Microscope) –SEM (Scanning Electron Microscope)

17. TEM Advantage Can magnify 1000 X’s more than a light microscope (Uh…1000 X 1000 = 1,000,000 X’s ) n Resolving power 0.2 nm

18. TEM Disadvantages n Must be in a vacuum (dead) n Sample must be VERY THIN (less than 0.2 nm)

19. TEM Images

20. SEM: Scanning Electron Microscope Advantages n Electron beam scans the surface n Resolution 10 nm n Magnifies 1,000,000 X’s

21. SEM Disadvantages n Must be in a vacuum (dead) n Cannot see internal structures

22. SEM Images n house fly n and its mouth

23. Choose Critter and Change Image n Molecular Expressions Microscopy Primer: Electron Microscopy Interactive Java Tutorials - Virtual Scanning Electron Microscopy Molecular Expressions Microscopy Primer: Electron Microscopy Interactive Java Tutorials - Virtual Scanning Electron Microscopy

24. SPM-Scanning Probe n Scanning Probe Microscope n Viewed ATOMS!!!!!!!!!!! n Does not need sample in a vacuum n Magnifies 10 million times

25. SPM Images (50 um X 1.4 um) n Steel Surface

26. SPM Images n DNA

27. FIRST TO VIEW ATOMS!!!

29. Label the parts: CHOICES: Diaphragm Objectives Ocular Coarse knob Fine knob Base Revolving nose piece Stage and stage clips Arm condenser

30. Label the parts: Ocular (eyepiece) Arm Coarse knob Fine knob (little) Revolving nose piece Objectives Stage and stage clips Diaphragm Condenser base

31. Always begin on lowest lens

32. n That is, as you increase magnification, the actual field of view becomes proportionally smaller. n 4OX 100X 400X

33. Use REVOLVING NOSEPIECE – don’t grab lenses

34. Eye Specimen

38. Depth of Field = to the thickness of the plane of focus

39. Viewing “F” with A Light Microscope n Which is an “F” put in a compound light and a dissection light microscope?

40. Field of View n What is the approximate width in mm? n In µm? (1 mm = 1000 µm) n 4 mm 4000 µm

41. Why use the letter “e?”

42. Do the math: n one millimeter (mm.) = 1,000 micrometers µm n So 5.5 mm = ________ µm n 5500 µm

43. NOTE!!!!!!!!!!!!!!!! n The field diameter at high power is proportional to the ratio of the low to high power objectives. n If 40X is 4000 µm n 400X is 400 µm

44. FD = field diameter n Low power FD X low magnification high power magnification = high power FD Use when object is between the mm markers

45. Why do you need to know Field Diameter? n You may wish to estimate the size of the specimens (e.g., cells) you will see in lab.

46. Field of View n What is the approximate size of this cell? n In mm? n In um? n If 5 fit across… n O.4 mm 400 µm

47. If the field of view in this question is 2 mm… How long is one cell? 2 mm

48. If the field of view in this question is 2 mm… If 3 cells fit across then, one cell is: 2mm 3 =.67 mm 2 mm

49. Wet Mount 1. Add drop of water 3. Add cover slip 2. Place Specimen on 4. Tap out bubbles slide

50. Making a Wet Mount Slide n Add drop of water n Add cover slip