Using A Microscope Pre-Lab

Use the file posted under the double lab modules titled "How to Use a Microscope" to help you with this assignment.

Use the image of the microscope to drag and identify each part. Make sure to scroll to view all possible choices.

a

b

c

d

e

f

g

h

i

j

diaphragm

fine adjustment knob

stage

eyepiece

objectives

tube

stage clips

arm

coarse adjustment knob

revolving nosepiece

Use the image of the microscope to drag and identify the function of each labeled part

a

b

c

d

e

f

g

h

i

j

Used to make large changes in focus

Reflects light up into the viewer's eye

Used to safely transport the microscope

Magnifying lens used to view the object

Allows for quick change of objectives

Changes the mount of light

Where the slide is placed

Provides magnification of 4X, 10X or 40X

Used to keep the slide in place

Used to make small changes in focus

Which two parts are most important to safely transporting the microscope

• arm

• base

• tube

• stage

• diaphragm

Describe what is meant by the term field of view when using a microscope.

• The maximum area visible while looking through the microscope.

• The distance between the stage and the objective lens that determines focus.

• The amount of light that passes through the diaphragm to illuminate the specimen.

• The level of detail visible under high-power magnification.

Which objective lens will give you the largest field of view?

• Low power

• Medium power

• High power

Proper microscope procedure is to start out with the objective lens as close to the slide as possible without making contact and use the coarse adjustment knob to move the objective lens away from the slide. Explain why it is important that you use the coarse adjustment knob to move the objective lens away from the slide and never towards the slide.

• Moving the objective lens toward the slide could cause the slide to hit the objective, damaging both the slide and the microscope.

• Moving the objective lens away from the slide increases magnification and produces a clearer image.

• Moving the objective lens away from the slide allows more light to pass through the diaphragm and improves illumination.

• Moving the objective lens toward the slide makes it easier to locate the specimen under low power.

Read over the section titled “use of the microscope” and put the following steps of using a microscope to view objects under high power in the correct order.

• Rotate the low power objective lens in place

• Focus using the fine adjustment knob

• Place a slide on the stage

• Rotate the high power objective lens in place

• Focus using the coarse adjustment knob

A student wishes to view her specimen under the highest power magnification allowed by her microscope. She starts by focusing her slide under low power using the fine adjustment knob. Once in focus she moves the slide to make sure the specimen is in the middle of the field of view. Then, she switches the objective to the high power objective. The slide is out of focus so she uses the coarse adjustment knob to refocus.

What are three things this student has done incorrectly?

• She used the fine adjustment knob instead of the coarse adjustment knob when focusing under low power.

• She moved the slide after it was focused under low power.

• She used the coarse adjustment knob while on high power to refocus.

• She centered the specimen in the field of view before switching objectives.

• She started viewing with the low power objective first.

Tags

NGSS.MS-ETS1-1

For all your answers type only a number with no "X".

The total magnification for microscope #1 is _.

(a)  

For all your answers type only a number with no "X".

The total magnification for microscope #2 is _.

(a)