MICROBIOLOGY LAB 5 2024 QUESTIONS WITH COMPLETE ANSWERS GRADED A+

1. When comparing a wet mount preparation to a commercially prepared slide, which of the following characteristics of Protozoa is best observed using a wet mount slide preparation?: mechanism of motility 2. What is the purpose of methylcellulose when preparing a wet mount of protozoa?: Methylcellulose increases the viscosity of the mount. 3. What structure is used for motility in Euglena?: flagellum -part of the motility-based group known as flagellates, which move by one or two flagella 4. significance and location of red spot in Euglena: located towards the anterior end. -sensory organ that detects light intensity. Protozoa are aquatic and light intensity varies at different depths in the environment. as a result of sensory information, the Euglena can change its depth to enhance photosynthesis and find food 5. Which of the following statements describes true motility?: Movement that appears to be directed from one position to another 6. Which of the following describes Brownian movement?: Vibratory movement of cells due to their bombardment by water molecules 7. Why are unstained bacterial specimens more difficult to view than stained specimens?: Stains provide contrast between the cells and the background. 8. When viewing a hanging drop, it is important to adjust the Abbe condenser using the iris diaphragm. What is the function of this part of the microscope?- : The Abbe condenser regulates the amount of light that passes upward from the light source and into the lens system. 9. Which statement is NOT true regarding protozoa?: Single-celled protozoa are similar in size to bacteria. 10. true statements of protozoa: some use flagella for motility, can be unicellular or multicellular (most are unicellular), are eukaryotes 11. What is the advantage of observing a hanging drop, compared to a wet mount preparation?: Motility and larger organisms are better viewed in a hanging drop due to the greater depth. 12. When viewing an unstained, live specimen, how do you distinguish be- tween true motility and Brownian movement?: True motility appears to be directed from one position to the next; Brownian movement appears as vibratory movement around a certain position that occurs at a constant rate. 13. Which of the following organisms does NOT exhibit true motility?: S.aureus 14. organisms the exhibit true motility: P. vulgaris, B. cereus, P. aeruginosa 15. Which of the following describes an advantage of observing stained rather than unstained bacterial specimens?: Stained preparations are heat fixed and adhere well to the slide. 16. Which of the following statements is CORRECT regarding the relative sizes of bacteria compared to protozoa and algae?: Prokaryotic bacterial cells are smaller than eukaryotic protozoa and algae. 17. S. aureus morphology: Staphylococcus aureus is Gram-positive, round shaped 18. B. cereus morphology: bacillis cereus is Gram-positive, rod-shaped 19. P. vulgaris morphology: proteus vulgaris is gram-negative, rod-shaped -inhabits the intestinal tracts of humans and animals. can be found in soil, water and fecal matter