Chapter 3 Flashcards
When using a microscope, the ability to show detail on the specimen is called the ____ _____ of the microscope.
Resolving power
What Lens of the microscope forms the magnified real image?
Objective lens
ocular lens
binomial lens
refractory light
The objective lens
_____ power × ____ power = total magnification
objective; ocular
In order to get the best resolution possible with a light microscope, you would want:
A. Long wavelengths of light
B. Short wavelengths of light
C. The wavelength doesn’t affect resolution
B. Short wavelengths of light
most widely used; specimen is darker than
surrounding field; used for live, unstained, and preserved,
stained specimens
Bright-field
brightly illuminated specimens surrounded by
______; used for live and unstained specimens
Dark-field
transforms subtle changes in light waves
passing through the specimen into differences in light
intensity, best for observing intracellular structures
Phase-contrast
Modified microscope with an ultraviolet radiation source and
filter.
Uses dyes that emit visible light when bombarded with
shorter UV rays. What kind of microscope is this?
Fluorescence Microscope
Uses a laser beam of light to scan the specimen.
Integrates images to allow focus on multiple depths or planes. This is Called a ____ microscope
Scanning Confocal Microscope
A powerful microscope used to observe the most minute specimens
Electron Microscopy
When using an electron microscope, Specimen requires special stains
or treatment.
True or false
true
When using an electron microscope Specimen is placed on___ ____ and when using a light microscope specimen is placed on ___ ___.
Copper mesh;Glass slide
What are the names of the 2 Types of Electron Microscopes ?
Transmit electron microscope (TEM) and
Scanning electron microscope (SEM)
____ ____ or ____ ____ ___allow examination
of characteristics of live cells: size, motility, shape, and arrangement
wet mounts; hanging drop mounts
____ ____ are made by drying and heating a film of specimen. This smear is stained using dyes to permit visualization of cells or cell parts.
Fixed mounts
What dye is cationic, positively charged chromophore?
Basic dyes
surfaces of microbes are negatively
charged and attract basic dyes. What kind of staining is this?
Positive staining
anionic, negatively charged chromophore is a ____ dye
acidic dye
when using a ____ stain, the microbe repels dye and the dye stains the background
Negative stain
A stain that uses only one dye and reveals shape, size, and
arrangement
Simple stains
which type of stain uses a primary stain and a counterstain to distinguish cell types or parts? (examples: Gram stain, acid-
fast stain, and endospore stain)
Differential stains
A stain that reveals certain cell parts not revealed by conventional methods.
Structural stains
The 6 I’s of Culturing Microbes are….
Inoculation
Isolation
Incubation
Inspection
Information gathering
Identification
Media can be classified according to three properties which are…
- Physical state
- Chemical composition
- Functional type
solid media containing beef extract,
peptone, and agar
Nutrient agar
contains pure organic and inorganic compounds
in an exact chemical formula
Synthetic
contains at least one ingredient
that is not chemically definable
Complex or nonsynthetic
contains complex organic substances such
as blood, serum, hemoglobin, or special growth factors
required by fastidious microbes
Enriched media
contains one or more ingredients that inhibit
growth of some microbes and encourage growth of the desired
microbes
Selective media
allows growth of several types of microbes
and produces visible differences among those microbes
Differential media
CHROMagar contains several
dyes and is used to diagnose
Urinary Tract Infections. The
patient’s sample is inoculated
and based on the color of the
colonies you can identify the
pathogen. CHROMagar is best
described as:
A. Enriched
B. Selective
C. Differential
D. Complex
C. Differential
contains sugars that can be fermented, converted to acids, and a pH indicator to
show this reaction. This is known as a _____ ______ medium
Carbohydrate fermentation medium
