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 to focus. The coarse - adjustment knob makes large adjustments, and the fine - adjustment knob makes small, precise adjustments.
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 large amount.
3. The fine - adjustment knob is used when you need to make small, precise focus adjustments, especially on high power or when the image is almost in focus but needs a little more clarity.
4. Common microscope objective powers are 4x (scanning), 10x (low - power), and 40x (high - power).
5. The magnification of a typical ocular lens is 10x.
6. The shortest objective is usually the scanning objective, often 4x.
7. You switch objectives by rotating the nosepiece.
8. The diaphragm controls the amount of light passing through the specimen.
9. You should carry the microscope with one hand on the arm and the other hand under the base to support its weight and keep it stable.
10. You can prevent the slide from slipping on the stage by using the stage clips to hold it in place.

Answer:

1. Coarse - adjustment knob, fine - adjustment knob
2. It can cause the objective lens to crash into the slide and damage the specimen or lens.
3. When small, precise focus adjustments are needed, especially on high power.
4. 4x, 10x, 40x
5. 10x
6. Scanning objective (usually 4x)
7. Rotate the nosepiece.
8. Diaphragm
9. One hand on the arm and the other hand under the base.
10. Use the stage clips.