1. What two structures on the microscope will you use to focus on your specimen? __ 2. Why should you never use the coarse adjustment knob on high power? __ 3. When do you use the fine adjustment knob? __ 4. Our microscopes have three objectives. What are their powers? __ 5. What is the magnification of the ocular lens? __ 6. What is the shortest objective called? __ 7. How do you switch objectives? __ 8. Which structure controls how much light passes through the specimen? __ 9. How should you carry the microscope? __ 10. How can you prevent your slide from slipping on the stage? __

1. Coarse adjustment knob and fine adjustment knob ### 2. It can damage the slide and lens. ### 3. For precise focusing at higher magnifications. ### 4. 4x, 10x, 40x ### 5. 10x ### 6. Scanning objective ### 7. Rotate the nosepiece. ### 8. Diaphragm ### 9. One hand under the base, one on the arm. ### 10. Use stage clips. Explanation 1. Identify focusing structures The coarse adjustment knob and the fine adjustment knob are used to focus on the specimen. 2. Explain caution with coarse adjustment The coarse adjustment knob should not be used on high power because it can cause the objective lens to crash into the slide, potentially damaging both. 3. Determine use of fine adjustment knob The fine adjustment knob is used for precise focusing after initially using the coarse adjustment knob, especially at higher magnifications. 4. List microscope objectives Commonly, microscopes have objectives with powers of 4x (scanning), 10x (low power), and 40x (high power). 5. State ocular lens magnification The magnification of the ocular lens is typically 10x. 6. Name the shortest objective The shortest objective is called the scanning objective. 7. Describe switching objectives Objectives are switched by rotating the nosepiece until the desired objective clicks into place. 8. Identify light control structure The diaphragm controls how much light passes through the specimen. 9. Explain proper carrying method Carry the microscope with one hand under the base and the other holding the arm for stability. 10. Prevent slide slipping Use stage clips to secure the slide and prevent it from slipping on the stage.