Question

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?

Explanation:

1. The coarse adjustment knob and fine adjustment knob are used for focusing. The coarse adjustment makes large - scale focus changes, and the fine adjustment makes small, precise changes.
2. Using the coarse adjustment knob on high power can cause the objective lens to crash into the slide and damage the specimen or the lens because it moves the stage up and down by a relatively large amount.
3. The fine adjustment knob is used to sharpen the focus when the specimen is already roughly in focus, especially on higher - power objectives.
4. Common microscope objectives have powers such as 4x (scanning), 10x (low - power), and 40x (high - power).
5. The magnification of the ocular lens is typically 10x.
6. The shortest objective is usually the scanning objective, often called the 4x objective.
7. Objectives are switched by rotating the nosepiece.
8. The diaphragm controls the amount of light passing through the specimen.
9. The microscope should be carried with one hand on the arm and the other hand supporting the base.
10. Slides can be prevented from slipping on the stage by using stage clips.

Answer:

1. Coarse adjustment knob, fine adjustment knob
2. It can cause the objective lens to crash into the slide and damage it.
3. To sharpen the focus when already roughly in focus, especially on high - power.
4. 4x, 10x, 40x
5. 10x
6. 4x objective (scanning objective)
7. Rotate the nosepiece.
8. Diaphragm
9. One hand on the arm, one hand on the base.
10. Use stage clips.