Microscopy

Question 1

How do you calculate magnification?

Answer 1

Image size / actual size

Question 2

What is resolution?

Answer 2

The shortest distance between two points that you can tell are separate

Question 3

What is magnification?

Answer 3

How many times larger the image is than the object.

Question 4

How do light microscopes work?

Answer 4

Light from the room reflects off the mirror and through the object, then through the objective lens (which spreads out the light rays), then through the eyepiece lens where the user looks.

Question 5

Compare electron microscopes to light microscopes.

Answer 5

Light microscopes are cheaper and easier to use, but they rely on light, so their resolution and magnification is limited, and they can’t help study subcellular structures, unlike electron microscopes.

Question 6

What is the magnification of the eyepiece lens?

Answer 6

10x

Question 7

Describe how to set up a microscope to observe an onion cell.

Answer 7

Stain a small, thin onion slice and stain it with iodine, and place it on a slide. Place the slide on the stage.
Looking side-on, turn the course focusing dial to lower the lowest-power objective lens as close to the slice as you can without them touching.
Look through the eyepiece lens and slowly turn the course focusing dial until the onion cell is in focus. Then, turn the fine focusing dial until the cell is clear.