AT- d

Question 1

How does light microscope work?

Answer 1

Light is focused through the condenser lens, then through the specimen.

Certain wavelengths of light are filtered

Light passes through an objective lens and then to eyepiece lens, producing a visible image

Question 2

What is an eyepiece graticule?

Answer 2

A glass disc that fits on top of the eyepiece lens that is marked with a fine scale from 1 to 100.

used to measure the cell being observed.

Question 3

How does an eyepiece graticule work?

Answer 3

eyepiece graticle is found in the eyepiece lens of an optical microscope.

microscope needs to be calibrated using eyepiece graticle, to measure the size of object being viewed
calibrated in combination with stage micrometer.

Question 4

How is an eyepiece graticule used to measure objects

Answer 4

place a prepared stage micrometer on the stage of a microscope

focus on the slide using the low-power objective lens

use high power/medium power objective lens to focus on an individual cell.

measure the length of the cell by counting the number of eyepiece divisions that fit into one division on micrometer scale.

work out the actual length of the cell in micrometers using your calibrated values

Question 5

When is light microscope at high power used?

Answer 5

to focus on the slide

Question 6

When is light microscope at low power used?

Answer 6

to focus on an individual cell