The Compound Microscope

Question 1

Two types of microscope

Answer 1

• light microscope
• electron microscope

Question 2

uses light as a source of illumination

Answer 2

light microscope

Question 3

Different kinds of light microscope

Answer 3

1. phase-contrast microscope
2. darkfield polarizing
3. UV

Question 4

typical student microscope

Answer 4

compound microscope

Question 5

Two types of lenses in compounds microscope

Answer 5

1. ocular lenses
2. objective lenses

Question 6

primarily responsible for magnification

Answer 6

lenses

Question 7

product of objective lens and ocular lens

Answer 7

total magnification

Question 8

marking on lenses are typically:

Answer 8

4X, 10X, 40X, 100X

Question 9

property of microscopes that allow the observer to distinguish structures that are separated by short distances

Answer 9

resolution/ resolving power

Question 10

magnification becomes useful if resolution is __

Answer 10

high

Question 11

wavelength of visible light

Answer 11

400-750 nm

Question 12

ordinary light microscope with oil immersion objective can distinguish two points approx. __ apart

Answer 12

0.2 μm

Question 13

• measure of the ability of the objective lens to separate in the image adjacent details that are present in the object
• distance between two points in the object that are just resolved in the image

Answer 13

limit of resolution (or resolving power)

Question 14

refers to the microscope’s ability to remain in approximate focus when switching from one objective to another

Answer 14

parfocality

Question 15

refers to distance between the specimen and the objective

Answer 15

working distance

Question 16

working distance as you move from 10X to 100X

Answer 16

from 8.3mm to 0.14mm

Question 17

of paramount importance to microbiologists

Answer 17

Oil immersion objective (OIO)

Question 18

main effect of immersion oil is to __ __ __

Answer 18

aberrant light rays (reduce bending of light)

Question 19

specimens to be viewed with a compound microscope are mounted on __ __

Answer 19

glass slides

Question 20

made by suspending microbes in liquid and covering the drop with a coverslip

Answer 20

wet mounts

Question 21

prepared by fixing while microorganisms or sections of organisms to the slide, staining the preparation, and gluing a glass coverslip on top

Answer 21

prepared stained microbial specimens

Question 22

Wet mount typically dries after ___

Answer 22

30-60 minutes

Question 23

wet mount enables the viewer to study __ __ and obtain information about __ __ and __

Answer 23

• living microorganisms
• natural pigmentation
• motility

Question 24

uses depression slides, which allow viewing of microbial movement or motility

Answer 24

hanging slide technique

Question 25

hanging slide technique enables the viewing of __ __ or __

Answer 25

• microbial movement
• motility