Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
64 Cards in this Set
- Front
- Back
____________ refers to the passage of light or electrons of various ___________ through lesnses to magnify objects and provide resolution and contranst so that those objects can be viewed and studied.
|
wavelengths |
|
_________ ___ is used in light microscopy to fill the space between the specimen and a lens to reduce light refraction and thurs increase the ____________ _________ and resolution.
|
numerical aperature |
|
Staining techniques and polarized light may be used to enhance __________ between an object and its background.
|
contrast
|
|
_______ ________ contain a single magnifying lens, whereas ________ _______ use a series of lenses for magnification.
|
compound microscopes |
|
The lens closes to the object being magnified is the _______ ______, several of which are mounted on a ________ __________. the lenses colsest to the eyes are ________ _______. ________ _______ lie beneath the stage and direct light throught the slide.
|
revolving nosepiece ocular lenses condenser lenses |
|
The magnification of the objective lens and the ocular lens are multiplied together to give _________ _________. |
total magnification |
|
a photograph of a microscopic image is a _____________. |
Micropgraph |
|
____________ ____________ provide a dark background for small or colorless specimens. |
dark-field microscopes |
|
_______ ____________, such as _______ ____________ and differential interference contrast (Nomarsk) microscopes, cause light rays that pass through a specimen to be out of phase with light rays that pass through the field, producing __________.
|
phase contrast contrast |
|
___________ ____________ use ultraviolet light and fluorescent dyes to fluoresce specimens and enhance __________. |
contrast |
|
A ____________ ____________ uses fluorescent dyes in conjunction with computers to provide three dimensional images of a specimen. |
confocal microscope |
|
A _______________ ____________ ______________ provides an image produced by the transmission of electrouns through a thinly sliced dehydrated specimen. |
transmission electron microscope |
|
A ______________ ____________ ___________ provides a three dimensional image by scattering electrouns from the metal coated surface of a specimen. |
scanning electron microscope |
|
Minuscule electrounic probes are used in ____________ _____________ _____________ and in ________ _______ _____________ to reveal details at the atomic level. |
atomic force microscopes |
|
Preparing to ________ organisms with dyes for light microscopy involves making a _______, or thin film, of the specimens on a slide and then either passing the slide through a flame (_____ _________) or applying a (__________ __________) to attach the specimens to the slide. ______ dyes or _______ dyes are used to stain different portions of an organism to aid viewing and identification.
|
smear heat fixation chemical fixation acidic basic |
|
__________ ________ involve the simple process of soaking the smear with one dye and then rinsing with water. ___________ ________ such as the _________ ________, ___________ _______, endospore stain, Gomori methenamin silver (GMS) stain, and the homtoxylin and eosin (HE) stain use more than one dye to differentiate different cells, chemicals, or structures.
|
Differential stains gram stain acidfast stain |
|
Gram-positive= Pink or Purple
|
purple |
|
Gram-negative= Pink or Purple
|
pink
|
|
The Gram stain procedure includes use of a ________ _______, a __________, a ______________ _______, and a _______________ which results in either a pink or purple depending on there cell walls.
|
mordant decolorizing counterstain |
|
The ______________ stain is used to differentiate cells with waxy cell walls. ____________ are stained by the Schaeffer-Fulton __________ stain procedure.
|
endospores endospore |
|
Dyes that stain the background and leave the cell colorless are called _________ (or ________ ________)
|
capsule stains |
|
______ are nonoverlapping groups of organisms that are studied and named in ____________. Carolus Linnaeus invented a system of ___________. |
taxonomy taxonomy |
|
order of taxonomy......
|
phylum class order family genus species |
|
Linnaeus gave each species a descriptive name consisting of a _________ name and _________ _________. This practice of naming organisms with two names is call ___________ ______________.
|
genus binomial nomenclature |
|
Carl Woese proposed the existence of three taxonomic _________ based on three cell types recealed by rRNA sequencing: _________, _________, and __________.
|
Eukarya Bacteria Archaea |
|
Taxonomists rely primarily on genetic differences revealed by morphological and metabolic dissimilarities to classify organisms. Species or strains withing species may be distinguished by using ________; ___________ test; nucleic acid analysis, particularly G+C content; or ______ ________ with bacteriophages, in wich unknown bacteria are identified by observing ________ (regions of a bacterial lawn where the phage has killed bacterial cells).
|
antisera; agglutination tests phage typing plaques |
|
microbiologist use _______________ ______, which involve stepwise choices between paired characteristics, to help them identify microbes. |
dichotomous keys |
|
A nanometer is ______________ than a micrometer. a. 10 times larger b. 10 times smaller c. 1000 times larger d. 1000 times smaller |
|
|
Resolution is best described as.... |
|
|
Curved glass lenses ___________ light. |
|
|
a. the thickness of the lens b. the curvature of the lens c. the speed of the light passing through the lens d. all of the above. |
|
|
a. magnification b. resolution c. wavelengths d. all of the above |
|
|
Which of the following types of microscopes produces a three dimensional image with a shadowed appearance? a. simple microscope b. differential interference contrast microscope c. fluorescent microscope d. transmission electron microscope |
|
|
Which of the following microscopes combines the greatest magnification with the best resolution? a. confocal microscope b. phase contrast microscope c. dark field microscope d. bright field microscope |
|
|
a. capsule stains b. endospore stains c. simple stains d. acid fast stains |
capsule stains |
|
In the binomial system of nomenclature, which term is always written in lowercase letters. a. kingdom b. domain c. genus d. specific epithet |
|
|
If an objective magnifies 40X and each binocular lens magnifies 15X, the total magnification of the object being viewed is ____________.
|
|
|
The type of fixation developed by Koch for bacteria is ____________.
|
|
|
which __________ (increases/decreases) resolution because __________ (more/fewer) light rays are involved. |
|
|
______________ refers to differences in intensity between two objects.
|
resolution
|
|
Cationic chromophores such as methylene blue ionically bond to ____________ (positively/negatively) charged chemicals such as DNA and proteins. |
|
|
parts of the microscope |
|
|
Gram Stain differentiates bacteria into 2 groups. Gram+ Gram+ will stain ___________ Gram+ cell wall has.... Gram- Gram- will stain ____________ Gram- cell wall has...... |
thick peptidoglycan layer pink thin peptidoglycan & outer membrane |
|
1.) crystal Violet- which is the -_____________ 2.) ______________- which is the -Mordant 3.) ______________- which is the -_____________ 4.) ______________- which is the -Counterstain |
1.) primary stain 2.) iodine 3.) ethanol or acetone =decolorizer 4.) safranin |
|
Gram- cells have thin cell walls which allows the __________ and __________ to be washed away with acetone or ethanol. Afterward these cells are __________.
|
& (mordant - iodine) clear |
|
explain how the principle "electrons travel as waves" applies to microscopy. |
|
|
critique the following definition of magnification given by a student on a microbiology test: "magnification makes things bigger." |
magnification is the apparent increase in size of an object.
|
|
|
|
|
put the following substances in the order they are used in a Gram stain: Counterstain, decolorizing agent, mordant, primary stain. |
|
|
why is latin used in taxanomic nomenclature? |
|
|
Give three characteristics of "specific epithet." |
|
|
how does the study of the nucleotide sequences of ribosomal RNA fit into a discussion of taxonomy? |
|
|
An atomic force microscope can magnify a living cell, whereas electron microscopes and scanning tunneling microscopes cannot. what requirement of electron and scanning tunneling microscopes preclude the imaging of living specimens? |
|
|
Why is the definition of species as "successfully interbreeding organisms" not satisfactory for most microorganisms? |
|
|
What is the function of immersion oil |
Immersion oil concentrates the light source through to the objective. without immersion oil light is refracted as it moves from the cover glass into the air and misses the objective lense. |
|
identify the two primary metric units used to measure the diameters of microbes
|
micrometer (um) = diameter of cell measurments nanometer (nm) = used to measure organelles in microbes and viruses |
|
list the metric units of length in order, from meter to nanometer.
|
decimeter centimeter millimeter micrometer nanometer |
|
curved glass lenses refract _______, and magnetic fields refract ___________ beams.
|
light electron |
|
an image magnified millions of times using a combination of lenses but the image still appears faint and blurry
|
empty magnification |
|
the clarity of an image is determined by the __________ & __________. |
resolution and contrast |
|
numerical aperature refers to....
|
i.e. when immersion oil is used the numerical aperature increases. |
|
resolution distance depends on what two things?
|
Wavelength and Numerical aperature |
|
staining increases __________. Using light that is in phase increases __________.
|
contrast |
|
four kinds of light microscopy and there uses: bright field = bacteria and nucleus dark field = endospores normarski = life unstainable samples |
|