1. A laboratory technique is illustrated in the diagram below. Explain why the coverslip is lowered at an angle.

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1 1. A laboratory technique is illustrated in the diagram below. Explain why the coverslip is lowered at an angle. 2. Base your answer to the following question on Which laboratory procedure is represented in the diagram below? 3. Base your answer to the following question on the diagram below, which represents a paramecium observed by a student using the low power objective (100 ) of a compound light microscope. 1 millimeter = 1000 micrometers Length of cell = Diameter divided by number of cells that would fit across the diameter. Explain the purpose of the technique demonstrated in the picture above. The approximate length of the paramecium is micrometers. 4. A student was observing cells with the microscope and noted that one cell occupied one-fourth of the diameter of the field of view. If the diameter of the field was 1.2 millimeters, what was the approximate length of the cell? Show your Work. µm

2 5. Base your answer to the following question on The diameter of a microscope field of view is illustrated below. 8. Base your answer to the following question on A cell in the field of view of a compound light microscope is shown in the diagram below. What is the approximate length of the cell in this field of view? A) 700 µm B) 1,000 µm C) 1,500 µm D) 2,000 µm 6. According to the diagram below, the diameter of the black circle shown in the field of view of the microscope is closest to In which direction should the slide be moved to center this cell in the microscopic field? Remember - objects under the microscope appear to move in the opposite direction of the slide. 9. Base your answer to the following question on The diagram below represents a cell in the field of view of a compound light microscope. A) 200 µm B) 600 µm C) 800 µm D) 1,400 µm 7. A specimen was viewed under the high-power objective of a compound light microscope. Its length was estimated to be 0.75 millimeter. What is the approximate length of the specimen in micrometers? A) B) 0.75 C) 75 D) 750 In which direction should the slide be moved on the microscope stage to center the cell in the field of view? A) toward A B) toward B C) toward C D) toward D

3 10. Base your answer to the following question on the diagrams below and on your knowledge of biology. 13. Base your answer to the following question on The diagram below shows how a coverslip should be lowered onto some single-celled organisms during the preparation of a wet mount. Which microscope setup would allow a student to see the largest field of view? What happens to the field of view as magnification increases? 11. The diagram below represents the letter "h" as seen in the low-power field of view of a compound light microscope. Which diagram best represents the field of view if the slide is not moved and the objective is switched to high power? A) B) C) D) 12. Which activity might lead to damage of a microscope and specimen? A) cleaning the ocular and objectives with lens paper B) focusing with low power first before moving the high power into position C) using the coarse adjustment to focus the specimen under high power D) adjusting the diaphragm to obtain more light under high powe Why is this a preferred procedure? A) The coverslip will prevent the slide from breaking. B) The organisms will be more evenly distributed. C) The possibility of breaking the coverslip is reduced. D) The possibility of trapping air bubbles is reduced. 14. Which structure in a stained cheek cell would most likely be visible when viewed through the high-power objective of a compound light microscope? A) cell wall B) ribosome C) chloroplast D) nucleolus 15. When onion cells are observed with a compound light microscope, which laboratory technique is used to make the nucleus more visible? A) centrifugation B) chromatography C) microdissection D) staining 16. The size of the image of a cell being examined with a microscope is determined by the A) light source and fine adjustment B) stage and stage clips C) objectives and ocular D) diaphragm and coarse adjustment 17. After switching from the high-power to the low-power objective lens of a compound light microscope, the area of the low-power field will appear A) larger and brighter B) smaller and brighter C) larger and darker D) smaller and darker

4 18. Base your answer to the following question on A compound light microscope is represented in the diagram below. Which microscope part is correctly paired with its function? A) A magnifies the image of the specimen B) B used for focusing only when the high-power objective is used C) C provides the field of view with the largest diameter D) D holds the specimen on the stage 19. Which part of a compound light microscope should a student adjust to allow more light to pass through a specimen? A) fine adjustment B) ocular C) diaphragm D) stage 20. Which part of a microscope should be used with the low-power objective, but not with the high-power objective? A) coarse adjustment B) fine adjustment C) diaphragm D) ocular

5 Answer Key Microscope Quiz Practice free response 1. Reduce air bubbles 2. To add stain without lifting up the coverslip µm 4. Length = diameter cells that fit across diameter Length = 1200 µm 4 cells 300 µm/cell 5. A 6. C 7. D 8. to the right and up 9. C 10. Microscope A 11. D 12. C 13. D 14. D 15. D 16. C 17. A 18. A 19. C 20. A As magnification increases, the field of view decreases.