Focus specimens using the compound microscope

1. Which of the following is TRUE about smears?

• Blood are prepared as smear.

• It cannot distinguish individual cells.

• Light colored or thin liquids are prepared in this way.

• It is used for living samples, transparent liquids, and aquatic samples.

2. When looking at an onion cell under a microscope, a thin slice of onion tissue is placed on a slide, then a small drop of dye is placed on the tissue. What should be done next?

• The coarse focus is adjusted until the cells become visible.

• A coverslip is placed over the onion tissue.

• A drawing of the onion cells should be made.

• The onion is cut into thin slices.

3. You are looking at an object under the microscope. What is the first step in focusing the microscope?

• Use the coarse adjustment on the highest power.

• Use the coarse adjustment on the lowest power.

• Use the fine adjustment on the highest power.

• Use the fine adjustment on the lowest power.

4. Which of the following is NOT the proper way of using the microscope?

• Use direct sunlight when the mirror is the light source.

• Use fine adjustment under high power objective lens.

• Use stage clips to hold the slide in place.

• Use lowest power objective lens first.

5. What are you going to do to bring the image into clear focus?

• Adjust the eyepiece and the revolving nosepiece to your desired view.

• Adjust the mirror and direct it towards the source of light.

• Turn the fine adjustment to attain the clearest image.

• Turn the coarse adjustment and bring it in focus.

6. Which of the following is the SECOND step on the sequence of how to focus the microscope on the specimen?

• Adjust the mirror towards the source of light.

• Move the stage as low as possible and using scanning objective. Use the coarse knob to focus: the image may be small at this magnification. Then move the mechanical stage until your focused image is also centered.

• Switch to the low power objective (10x). Use the coarse knob to refocus and move the mechanical stage to re-center your image.

• Switch to the high power objective (40x). Then use the fine adjustment knob to focus specimens.

7. If you move the slide left while viewing, in which direction will it appear to move?

• Right

• Left

• Up

• Down

8. Which direction will the slide go if you move it down while looking through the microscope?

• Right

• Left

• Up

• Down

9. The higher the magnification, the __________ you see of the specimen.

• Closer

• Farther

• Lower

• More

10. What is the total magnification of a specimen viewed with a 10x eyepiece and 40x objective lens?

• 30x

• 50x

• 400x

• 4000x