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Requred drawings:

1. Amoeba proteus. whole mount. Note general form of the cell. The large nucleus contains many small nucleoli. There is conspicuous contractile vacuole that is usually visible (especially under phase contrast illumination). Note food vacuoles with prey. The uroid is a special region at the back end of the cell. It usually looks rather wrinkled. Membrane is being taken up in this region as the cell moves forward. There are also often an accumulation of food vacuoles in this region. Slide 1 17 x 97

2. Amoeba proteus. whole mount. Note general form of the cell. The large nucleus contains many small nucleoli. There is conspicuous contractile vacuole that is usually visible (especially under phase contrast illumination). Note food vacuoles with prey. The uroid is a special region at the back end of the cell (toward 6:00). It usually looks rather wrinkled. Membrane is being taken up in this region as the cell moves forward. There are also often an accumulation of food vacuoles in this region. Notice that at the front end of the cell (toward 12:00) there is a euglenoid that is nearly engulfed. Slide 2 14 x 98

3. Amoeba proteus. whole mount. Note general form of the cell. The large nucleus contains many small nucleoli. There is conspicuous contractile vacuole that is usually visible (especially under phase contrast illumination). Note food vacuoles with prey. The uroid is a special region at the back end of the cell. It usually looks rather wrinkled. Membrane is being taken up in this region as the cell moves forward. There are also often an accumulation of food vacuoles in this region.

There is another type of amoeba, Acanthamoeba, immediately adjacent to the larger A. proteus cell. Notice the difference in general morphology, the nucleus with a large endosome (nucleolus). slide 3 6 x 97

4. - 6. Acanthamoeba. Note general form of the cell, the nucleus with large endosome (nucleolus), pseudopodia, food vacuoles etc.

7. - 8. Amoeba proteus. Sections. Note nucleus with many small nucleoli., endoplasm containing food vacuoles and many vesicles; ectoplasm has a generally more uniform appearance. Notice sections of pseudopodia. Notice that there are many symbiotic bacteria in the cytoplasm (small redish objects).

9. - 10. Chaos. sections. A large amoeba similar to Amoeba. The division into ectoplasm and endoplasm is more distinct than in Amoeba. Endoplasm contains many smaller nuclei each with many small nucleoli. Note vesicles and vacuoles in the endoplasm and uniform cytoplasmic gel in the ectoplasmic region.

11. Entamoeba gingivalis. a commensal amoebae found in the mouth (typically in infected gum clefts. Notice single large pseudopodium, nucleus and food vacuoles. The dark objects in food vacuoles are nuclei of pus cells. This smear contains bacteria, pus cells, epithelial cells and amoebae.

12. Entamoeba histolytica. in lesion is gut epithelium. Examine first with 10x objective. Note lesion (ulcer) in gut epithelium. It is a depression in the epithelium where the cells have been eaten away. Using the 40x objective locate amoebae in the ulcer. They are large grey cells with relatively uniform cytoplasm and pale hollow-looking nuclei.

13. Entamoeba histolytica. in infected lung. Note alveolus filled with large oval cells. In normal tissue the alveolus (air sac) would be empty.

14. - 15. Entamoeba histolytica in epithelium of the gut. Note oval cells with large nuclei. Look in area of cross hairs.

16. Entamoeba histolytica in fecal smear.

17. Iodamoeba in fecal smear.

18. Entamoeba coli in fecal smear. This entamoeba is a commensal.

19. Arcella, a testate amoeba. Stained to show nucleic acids (blue). Note strongly stained chromidial net (RER) involved in synthesis of proteins for secretory granules used to form the test of the daughter cell at division. Cells with deeply stained chromidial net were fixed early I the cell cycle. Cells fixed at later stages have reduced staining in the chromidial net and deeper stain in the endosome (nucleolus). In cells at later stages in the cycle, secretory granules are apparent. (See # 21).

20. Arcella, a testate amoeba. Stained to show nucleic acids (red-orange). Note strongly stained chromidial net (RER) involved in synthesis of proteins for secretory granules used to form the test of the daughter cell at division. Cells with deeply stained chromidial net were fixed early I the cell cycle. Cells fixed at later stages have reduced staining in the chromidial net and deeper stain in the endosome (nucleolus). In cells at later stages in the cycle, secretory granules are apparent. (See # 21). Very good specimen.

21 Arcella stained to show secretory granules, chromidial net, nuclei and other morphological features. This is a nice specimen. There are lots of things to see.

22. - 24. Centropyxis, a testate amoeba. Note test morphology (shaped like bed pan with spines!). Note aperture in test, pink cytoplasm, purple chromidial net, purple oblong nucleus at one side of the cell. Use 10x and 40x objectives as needed.

25.-28. Difflugia. A testate amoeba with a test composed of sand grains cemented together with organic material. Cytoplasm is stained pink. Note pseudopodia. The nucleus is ovoid, stained a deeper red color and located in the upper part of the cell, away from the aperture. Look briefly at several specimens. Despite the irregularity of the sand

29. - 30. Physarum, section through plasmodium. Note that there are many nuclei (with conspicuous endosome) in the cytoplasm. Remember that the entire plasmodium is a single cell. The heavily stained side of the plasmodium is away from the substratum. What do you think that the stain gradient means?