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Chapter 1: METHODS
Methods6e.doc
1. Describe the steps involved in obtaining H & E stained sections.
2. How does formaldehyde react with tissue? Does formaldehyde preserve membranes well?
3. Which cellular components stain blue with H & E?
4. What techniques and fixatives must be used to preserve neutral lipids for microscopic examination?
5. Which two stains are commonly used to stain elastic fibers?
6. What procedure is used to reveal reticular fibers and the basement membrane?
7. Why do surgeons often use frozen sections? What are the advantages of using frozen sections?
8. What is ergastoplasm?
9. Give three examples of large molecules that are routinely lost during fixation with aqueous solutions.
10. What are the commonly used basic dyes? What components are stained by basic dyes? How is the intensity of the stain related to pH?
11. What is unusual about the binding of hematoxylin that makes it well suited to be combined with acidic dyes?
12. What are the commonly used acidic dyes? What components are stained by acidic dyes?
13. What substances within cells and in the extracellular matrix display basophilia?
14. What is heterochromatin? What is euchromatin?
15. What is metachromasia?
16. What does the PAS reaction stain?
17. What does the Feulgen reaction reveal?
18. How is the Feulgen reaction useful in the diagnosis of cancers?
19. Describe the methods used to determine whether a cell possesses a given enzyme?
20. Why might one use antibodies for processing histological materials? How can antibodies be used to visualize histological material?
21. What is the difference between polyclonal and monoclonal antibodies?
22. What is the difference between direct and indirect labeling with antibodies?
23. Other than fluorescent markers, what else can be used to tag antibodies such that they can be observed with microscopy?
24. What technique allows histologists to detect specific sequences of RNA or DNA in a cell?
25. What is FISH and how does it work? How might it be used to detect Down syndrome (Trisomy 21)?
26. What are the steps for autoradiography and how can autoradiography be used to demonstrate dividing cells?
27. Why must most biological material be stained for microscopic examination with a bright-field microscope?
28. What is an artifact?
29. What property makes the phase-contrast microscope well-suited for examining living tissue?
30. How does a dark-field microscope work?
31. What is the purpose of two sets of filters in a fluorescence microscope?
32. What are the major advantages of a confocal scanning microscope?
33. How does the preparation of tissue for TEM differ from that for conventional light microscopy?
34. What is the purpose of osmium tetroxide in preparing tissue for TEM?
35. What does the “freeze fracture” method allow one to see?
36. What is the difference between transmission electron microcopy and scanning electron microscopy? Since paraffin is not used for embedding a specimen prior to sectioning, what is used and why?
37. What is atomic force microscopy very well suited for?