Micro Bio Chp 3 Exam 1
What is the function of the cellular structure indicated by "c" in Figure 3.2?
provide shape attach to surfaces and protect from dehydration
Which of the following have a periplasmic space?
Gram negative bacteria only
Which of the following prokaryotic cells contain an outer membrane?
Gram negative bacteria only
What is the function of the cellular structure indicated by "p" in figure 3-3?
ATP synthesis
Viruses are generally measured in ?
Nanometers
Which of the following is an INCORRECT pairing?
numerical aperture; curved glass
The ability of a lens to gather light is referred to as its
numerical apertue
Which of the following are magnifying lenses?
both objective and the ocular
If you were trying to visualize flagella without staining, which microscope would you use?
Phase Contrast
Why does immersion oil improve resolution?
It increases numerical aperture and maintains a uniform light speed
You are shown a micrograph from a light microscope in which the specimens appear bright compared to the background. The micrograph is probably from an ______ microscope.
Dark field
The microscope preferred for viewing living specimens is the _____ microscope.
phase-contrast
Which of the following is NOT associated with an electron microscope?
a prism
All of the following are types of light microscopes EXCEPT
scanning tunneling
Which of the following microscopes produces the highest resolution images?
atomic force
If a microbiology lab student left the safranin out of the Gram stain procedure, what would be the result?
Gram positive cells would be purple and Gram negative cells would be colorless
All of the following are common to both the Gram stain and the acid-fast stain EXCEPT
a chemical mordant
Safrainin dye is used as the counterstain in ______ stains.
Both gram stain and endospore
Heat is used to drive the stain into cells in the ____ staining procedures.
both acid-fast and endospore stains
Carbolfuchsin is the ____ in the acid fast stain.
primary stain
A sample is prepared using osminum tetroxide as a stain. This sample has been prepared for an _____ microscope.
electron
The kingdoms included in the Linnaeus system of classification are
Animalia and Plantae
The rules of naming organisms are called
nomencalture
Species and strains of microbes can be distinguished from one another phenotypically using
serological tests
Which of the following is NOT a characteristic of a genus name?
It is usually an adjective
Carl Woese proposed the concept of the domain based on differences of which of the following cellular molecules?
ribosomal RNA
Which of the following classification methods relies on the morphology of organisms?
physical (phenotypic) characteristics
A cell's G + C ratio is associated with which of the following classification methods?
analysis of nucleic acids
Viruses are not included in the taxonomic scheme proposed by Carl Woese because they lack?
Ribosomal RNA
Why have some microbiologist proposed using ribosomal RNA as the basis for defining bacterial species?
Bacteria are not interbreeding populations, and ribosomal RNAs are highly conserved genes present in all prokaryotes
Which of the following phenomena produces magnification?
the refraction of radiation as it passes through a lens
A virologist wants to observe the surface features of virus particles she is studying. Which of the following microscopes would NOT be useful for her observation?
differential interference contrast
A structure that appears in a transmission electron micrograph but is NOT actually present in the specimen is known as a ____
artifact
Which of the following statements about transmission electron microscopy is FALSE?
Glass lenses are used
Acidic Dyes ___
are negatively charged and work best at low pH
A thin film of microbes on a slide is a ____
smear
The Gram stain works because of differences in the _____ of bacteria.
Cell walls
the primary goal of modern taxonomists is to
understand the phylogenetic relationships between organisms
Why are modern light microscopes better than the ones Leeuwenhoek used?
modern microscopes have a fivefold better resolution
In the Gram stain procedure, iodine serves as a
mordant
What role does safranin play in the Gram stain procedure?
counterstain
In Gram staining ethanol-acetone is used as a
decolorizing agent
A sample from a patient is prepared using the Gomori methenamine silver stain. What type of microbe is suspected of being present?
Fungus
Tungsten is a reagent used in the
electron microscopy stain
The ____ stain is one in which eosin is used
negative
Tannic acid is a mordant (chemical fictive) used in the ____ stain.
flagellar
Methylene blue can be used to stain DNA because it
forms ionic bonds with DNA
The _____ stain makes use of malachite green.
endospore
The most appropriate unit of measurement for intact archaea is the
micrometer
The limits of resolution of atomic force microscopes are in the range of
nanometers
the size of a port tapeworm is generally described in terms of
meters(m)
A measurement of a mcirobe is reported as 1 x 10 -6m, also known as
micrometers (um)
One-thousandths of a meter is a
millimeter (mm)
Bacteria and many other microbes do not ______ and therefore do not fit Linneaus' definition species
reproduce sexually