ch.2 stuff

Question 1

Types of compound light microscopy

Answer 1

Brightfield
Darkfield
Phase contrast

Question 2

Resolution

Answer 2

Ability of lenses to distinguish 2 points

Question 3

What’s immersion oil used for?

Answer 3

To keep light from refracting

Question 4

Brightfield Illumination

Answer 4

Dark objects visible against light background
Light reflected off specimen does not enter objective lense

Question 5

Darkfield Illumination

Answer 5

Light objects visible against dark bakground
Opaque disk placed in condenser
Only light reflected off specimen enters objective lense

Question 6

Phase Contrast

Answer 6

Allows us to see living organisms and internal cell structures
Brings together 2 sets of light rays, direct rays, and diffracted rays

Question 7

Staining

Answer 7

Coloring of microorganisms with dye

Question 8

Smear

Answer 8

Thin layer of material spread over a slide

Question 9

Fixed

Answer 9

When microorganisms attach to the slide using head, which kills the microorganisms

Question 10

In basic dyes , chromophore is ?

Answer 10

Cation

Question 11

In acidic dyes, chromophore is?

Answer 11

Anion

Question 12

What is negative staining?

Answer 12

Staining the background instead of the cell

Question 13

What is a simple stain?

Answer 13

Use of a basic dye

Question 14

What do simple stains do?

Answer 14

Highlight entire microorganism to visualize cell shapes and structures

Question 15

What is a mordant used for?

Answer 15

Is used to hold/ intensify the stain

Question 16

What are the most common used differential stains?

Answer 16

Gram Stain
Acid Fast Stain

Question 17

Gram Staining steps

Answer 17

Apply crystal violet (purple dye)
Apply iodine (mordant)
Alcohol wash (decolorization)
Apply safranin (Counterstain)

Question 18

What color is gram negative?

Answer 18

Pink

Question 19

What color is gram positive?

Answer 19

Purple

Question 20

What do acid fast stains bind to?

Answer 20

To bacteria that have waxy material in their cell walls, which are not decolorized by acid alcohol

Question 21

True or false: Mycobacterium and Nocardia keep their primary dye Carbolfuschin despite decolorization of acid alcohol?

Answer 21

True