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Chapter 5: EPITHELIAL TISSUE
Epithelia6e.doc
1. Where are epithelial tissues found?
2. What do epithelial tissues and epitheliod tissues have in common, and how do they
differ?
3. What two criteria are use to classify the various epithelia of the body?
4. Based on Table 5.1, what are the 8 classifications of epithelia?
5. In a stratified epithelium, which cells are used to classify according to shape?
6. What are the two special categories of epithelium and what is characteristic of each?
7. What are the three specific forms of simple squamous epithelium that line blood
vessels and body cavities and where are they located?
8. Based on Table 5.1 and the text, what are some of the functions of the various types of
epithelia?
9. What are the three domains of an epithelial cell that are responsible for cell polarity?
10. What are microvilli?
11. What are cilia?
12. What two cellular functions seem to be associated with these structures?
13. How is the number of microvilli related to the magnitude of transepithelial transport?
14. What is a terminal web?
15. Why is the term stereocilia rather misleading?
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16. What are basal bodies?
17. What is the arrangement of microtubules in a motile cilium?
18. What are the two strokes of a cilium?
19. In most cuboidal and columnar epithelia that has been stained with silver, what is
the small dark line that appears between the apex of cells as viewed in a horizontal
section and is seen especially well in electron micrographs?
20. What three cellular attachments comprise the structure referred to in the previous
question? (These three components can be resolved only with electron microscopy.)
21. Which component of the junctional complex serves to create a barrier between cells
and restricts the free passage of substances between adjacent epithelial cells?
22. What structure is responsible for preventing the diffusion of membrane proteins from
the basal and lateral surfaces to the apical surface of some epithelia and thus contributes
the cell polarity?
23. Which components of the junctional complex guard against the physical disruption
of the barrier and mechanical separation of adjacent epithelial cells?
24. Which of the three structures is found in places other than the junctional complex
(that is, other than the lateral domain)?
25. What is a CAM?
26. Thought question: When dissociating cells from adjacent cells in the laboratory, why
is the dissociation procedure commonly done in a solution from which Ca++ is excluded?
27. Which category of CAM is particularly well suited for allowing an epithelial cell to
interact with molecules the extracellular matrix?
28. What is the main function of the zonula adherens?
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29. Give two names for the structure characterized by electron-dense plaques with
intermediate filaments attached to them?
30. How does the location of a desmosome differ from the location of a
hemidesmosome?
31. What are some of the functions of gap junctions?
32. What is a lateral plication and in what types of epithelia are they most obvious?
33. Where is the basement membrane located and what stains are well-suited to reveal
the basement membrane?
34. What is the confusion surrounding the use of the terms basal lamina and basement
membrane?
35. What is the difference between a basal lamina and an external lamina?
36. What is the role of laminin?
37. What are the main functions of the basal lamina?
38. What structures are involved in mechanosensitivity?
39. What structure is abundant in locations that must be resistant to mechanical stress?
40. In what ways are exocrine glands distinguished from endocrine glands?
41. What are the three mechanisms of secretion from exocrine glands? Which one is
associated with the death of the cell?
42. Because glandular tissue can be organized in many ways, be familiar with the
terminology in the left-most column of Table 5.6. (Note: can you find the pair
whose labels have been swapped?)
43. What is an acinus?
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44. What is the difference between a mucus secretion and a serous secretion?
45. What is a mucous membrane and where are these located?
46. What is a serous membrane and where are these located?