Microscope Lab Quiz

1. What is the total magnification produced by a microscope, using a 10X ocular lens and a 10X objective lens?

2. Which of the following describes proper microscope care and technique.
Be sure to carry the microscope upright, with one hand on the arm and the other under the base.
To protect the optics of the microscope, place it down gently and don't drag it across the tabletop.
Always begin focusing with the lowest power lens available.
Only use the coarse focus knob with the scanning and low power lenses.
All the above are examples of correct microscope care and technique.

3. Turning which of the following knobs moves the objective lenses the greatest vertical distance?
coarse focus knob
fine focus knob

4. Resolution is the ability to see two objects as separate.

5. Which objective lens is the longest?
scanning lens
low power lens
high power lens
oil immersion lens

6. Which of the following regulates the amount of light passing through the slide specimen on the microscope stage?
objective lens
iris diaphragm lever
fine focus knob

7. An increase in magnification causes
a decrease in the field of view.
a decrease in the working distance.
a decrease in the depth of field.
all of the above.

8. Working distance is the
distance from your house to your job.
distance the microscope nosepiece travels using the coarse focus knob.
distance from the bottom of the objective lens to the specimen.
distance the specimen can travel across the microscope stage.

9. The magnification of a light microscope is limited to 1000X by the resolving power of the instrument.

10. When using the oil immersion lens, you should raise the objective lenses for easy application of an oil droplet to the slide.

11. Why must a small object seen through the ocular lens be centered in the field of view, before changing to a higher power objective lens?
to prevent damage to the objective lens
to compensate for the decrease in resolving power of the lens
to prevent its disappearance due to the decrease in the field of view
to prevent eyestrain

12. A parfocal microscope allows you to quickly focus using the low power or scanning lens and then, to switch to a higher power lens with only a minimal adjustment of the fine focus knob.

13. Why is it necessary to adjust the amount of light after changing objective lenses?
Higher magnification lenses require more light.
Proper lighting is needed to see specimen details.
The lens aperture decreases with higher magnification lenses.
All of the above.

14. One meter equals
100 cm.
1000 mm.
1,000,000 microns.
All of the above.

15. A grid slide (with 1 mm squares) is used to directly measure
the field of view.
the depth of field.
the working distance.

16. If you prepare a wet mount slide and observe a large empty circle with dark edges, you are most likely seeing an air bubble.

17. If the field of view of the low power (10x) objective lens is 4 mm, what would the field of view be for the oil immersion (100x) lens?
400 microns
4 mm
0 .4 cm
None of the above.

18. Depth of field is best demonstrated with
a slide showing the letter e.
a slide containing overlapping threads.
a wet mount slide preparation.
the oil immersion lens.

19. When the letter e slide is viewed with the microscope, it appears
right side up.
right side up and backwards.
upside down.
upside down and backwards.

20. A wet mount is
a freshly prepared slide.
a horse left out in the rain.