Chapter 2 Flashcards
The introduction of a bacterial sample into media to
culture microbes
inoculation
Media that encourages the growth of some
organisms but suppresses the growth of others
Selective Media
This media causes an observable change (color or change in pH) in the
medium when a particular biochemical reactions
occurs
Differential Media
Media that contains special nutrients that allow growth
of a particular organism that might not otherwise
be present in sufficient numbers.
Enrichment Media
A temperature-controlled chamber to encourage the
multiplication of microbes
Incubator
A macroscopic cluster of cells appearing on a solid
medium arising from the multiplication of a single
cell
Colony
Method commonly used to achieve colony isolation
Streak Plate Technique
This lens forms the initial image of the specimen
called the Real Image
Objective lens
This lens forms the Virtual Image, which is the
magnified image that is received by the retina and
perceived by the brain.
Ocular lens
The capacity of an optical system to distinguish or
separate between two adjacent objects or points
from one another
Resolution
Refers to the degree of contrast between an
specimen and its surroundings
Contrast
Cells are suspended in water or broth to maintain
viability and provide space for locomotion.
Wet mount prep (ex. Hanging drop slide)
Occurs when the slide is passed through an open
flame several times.
Heat Fixation
Purpose of heat fixation
- Kills the microbe
- adheres the microbe to the slide
- breaks down the membrane for better stain retention
_____ dyes have a positive charge
Basic
______dyes have a negative charge
Acidic
Dye sticks to the specimen and gives it color
Positive staining technique (requires a basic dye)
Dye does not stick to the specimen but settles some
distance from its outer boundary within the background
Negative staining technique (requires an acidic dye)
Uses two differently colored dyes: the primary dye
and the counter-stain to distinguish cell types or
parts
Differential Staining Technique
Causes all the cells in the smear to appear more or
less the same color, used to
Reveal shape, size, and arrangement
Simple Staining Technique
Different results in the Gram stain are due to
differences in the structure of the _________ and
how it reacts to the series of reagents applied to the
cells
Cell Wall
Originated as a method to detect Mycobacterium
tuberculosis
Acid Fast Staining
Stain distinguishes between spores and vegetative
cells
Endospore Stain
Proper order for Gram Staining
Crystal Violet, Iodine, Alcohol Rinse and Safranin
Used to emphasize cell parts that are not revealed by conventional staining methods
Special Stain
Gram positive cells are stained
purple
Gram negative cells are stained
pink
Acid fast positive cells are stained
pink
Acid fast negative cells are stained
blue
