Question 1

Which part of the compound microscope is responsible for collecting and concentrating light upward through the object on the stage?

Accepted Answer

Abbe condenser

Question 2

Why is immersion oil used with the oil-immersion objective lens?

Accepted Answer

To improve resolution by reducing light scattering

Question 3

If you use a 10x ocular lens and a 40x objective lens, what is the total magnification achieved?

Accepted Answer

$$10 	imes 40 = 400$$

Question 4

Which adjustment knob should you use to bring an object into sharp focus after it is already visible under low power?

Accepted Answer

Fine adjustment knob

Question 5

What is the main advantage of parfocal objective lenses?

Accepted Answer

They remain in focus when switching between objectives

Question 6

Which of the following is the best way to adjust the amount of light entering your specimen?

Accepted Answer

By opening or closing the iris diaphragm

Question 7

If you see moving particles in a hazy visual field while using the oil-immersion lens, what is the most likely cause?

Accepted Answer

There are bubbles in the immersion oil

Question 8

What is the function of the mechanical stage on a compound microscope?

Accepted Answer

To move the slide in vertical and horizontal directions

Question 9

Which of the following steps is NOT recommended when putting away a microscope after use?

Accepted Answer

Leave oil on the oil-immersion objective

Question 10

If a 5x ocular lens is used with a 100x oil-immersion objective, what is the maximum total magnification?

Accepted Answer

$$5 	imes 100 = 500$$

Question 11

Which part of the microscope should you NEVER use to carry the instrument?

Accepted Answer

The part that holds the lenses

Question 12

What would you most likely observe if you forgot to use oil with the oil-immersion lens?

Accepted Answer

A blurry image with poor resolution

Question 13

Which of the following best describes the difference between magnification and resolution?

Accepted Answer

Magnification is the ability to enlarge an image; resolution is the ability to distinguish detail

Question 14

A student is having trouble seeing their specimen clearly under high power. Which troubleshooting step should they try first?

Accepted Answer

Open the iris diaphragm to increase light

Question 15

Why is it important to use only lens paper to clean microscope lenses?

Accepted Answer

Other materials may scratch or damage the lenses

Question 16

Which part of the microscope controls the amount of light emitted by the bulb?

Accepted Answer

Rheostat control knob

Question 17

A student switches from the low-power to the high-power objective and the image remains in focus. What feature of the microscope allows this?

Accepted Answer

Parfocal objectives

Question 18

Which of the following is a correct step in focusing a specimen under the microscope?

Accepted Answer

Use the fine adjustment knob for final focusing under high power

Question 19

What is the primary reason for reporting any defects or damage to the microscope before use?

Accepted Answer

To ensure the microscope functions properly and prevent further damage

Question 20

Which of the following best explains why more light is needed to view stained preparations compared to unstained ones?

Accepted Answer

Stained preparations absorb more light

Microscopy: Structure, Function, and Use of the Compound Microscope in Microbiology

Study Guide - Practice Questions