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783 Cards in this Set

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agar
A gelatin-like solidifying agent used in laboratory culture media.
animalcules
Tiny, rapidly swimming animals first observed under a
microscope by Antonie van Leeuwenhoek in the 1670s.
gene therapy
The replacement of a defective gene with a normal one in patients suffering from a wide variety of genetic diseases.
biotechnology
A process widely employed by various industries that uses
microbes to solve biological problems; to produce large
quantities of useful items such as antibiotics, vitamins, and food
supplements; and to degrade toxic materials (especially in raw
sewage).
germ theory of
disease
The belief that microbes will grow in humans and are the cause
of diseases that spread from person to person and town to town.
hypothesis
A suggested explanation for observations relating to a specific
scientific phenomenon.
Koch postulates
Four requirements developed by Robert Koch in the 1870s that
must be satisfied in order to establish that an organism is the
cause of a disease: show that a given organism exists in animals
infected with the specific disease but not in animals that are not
infected with the disease; obtain a pure culture of the organism;
produce the same symptoms seen in the infected animals by
inoculating healthy animals with this isolate; and isolate the
identical microbe from the newly infected animal.
pure culture
A group of microorganisms consisting of a single species of cells
with no external contamination.
lysozymes
Enzymes discovered by Alexander Fleming in the early
twentieth century that destroy bacteria by degrading bacterial
cell walls.
scientific method
A logic-based process scientists use to make observations about
a specific phenomenon, develop a hypothesis to explain these
observations, and arrive at provable conclusions.
microbes
Tiny, medically relevant organisms including prions, viruses,
bacteria, fungi, and parasites.
spontaneous
generation
The notion that microbes develop without any cellular parentage.
microbiology
The study of a variety of organisms that require a microscope to
be seen.
bacteria
Millions of forms of small, single-celled living microorganisms.
penicillin
The first true antibiotic used to kill bacteria during the twentieth
century.
binomial system
A two-titled naming system for organisms that includes the
organism’s genus and species.
biovars
Biological variants that exist between one or several genes in an
organism.
domain
The highest level of nomenclature division.
Cyanobacteria
Once thought to be blue-green algae, this form of bacteria uses
sunlight to produce carbohydrates and fix nitrogen from the air,
creating a bad taste and odor in drinking water supplies during
summertime. Cyanobacteria perform a major role in the
worldwide production of oxygen.
eukaryotes
The various species of the domain Eukarya, which includes all
organisms except bacteria. Eukaryotes contain a true (eu)
nucleus.
nomenclature
nomenclature
A process of naming and classifying microbes.
prokaryotes
Bacterial organisms that have no nucleus. The term derives from
the Greek terms “pro” (meaning before) and “kary” (meaning
nucleus).
differential strain
A staining procedure that differentiates between two common
types of bacteria.
serovars
Serological variants that exist between one or several genes in an
organism.
electron microscopy
High-resolution microscope observation that uses electrons to
illuminate tiny virus particles.
strains
Variations between organisms that exist in one or several genes.
medium
A nutritious extract or mixture of materials that will support the
growth of microbes.
taxonomy
The practice of naming and classifying microbes or other living
organisms.
scanning electron
microscopy
A viewing process in which scattered electrons are detected and
the object’s surface is reconstructed by computer technology;
especially good for visualizing surface structures.
dark-field
microscopy
A modification of the light microscope in which light coming
directly through the specimen is blocked out so that light
reflected off the bacteria can be readily seen.
staining
A dye or colored material that is added to organisms to improve
contrast and the ability to recognize microbes readily.
transmission
electron microscopy
A process in which electrons pass through a specimen and heavy
metals pile up around the virus and scatter electrons. This leaves
dark areas that reflect the viral outline on the viewing screen.
chromosome
A single piece of double-stranded DNA composed of thousands of genes.
The two strands are complementary so that they always pair in a certain order.
acids
Substances that have an excess of H+ ions.
codons
Nucleic acid letters read in triplets so that each possible three letter word codes for a specific amino acid.
Codons act as a
blueprint for how proteins will be organized.
adenine
A base that opposes thymidine (T) within the two strands of
DNA.
cytosine
A base that opposes guanine within the two strands of DNA.
bases
Substances that have an excess of OH− ions.
deoxyribonucleic acid
A variety of nucleic acid and, along with ribonucleic acid, one of two types of molecules that encode genetic information.
cholesterols
Waxy, lipid substances found in the bloodstreams and cells of
animals.
chromosome
A single piece of double-stranded DNA composed of thousands of genes. The two strands are complementary so that they always pair in a certain order.
ergosterols
Lipid components found in fungi that serve the same purpose as cholesterol in animals.
codons
Nucleic acid letters read in triplets so that each possible threeletter word codes for a specific amino acid. Codons act as a blueprint for how proteins will be organized.
gene
A string of three-letter codons that is usually 300 to 1000 base
pairs long.
cytosine
A base that opposes guanine within the two strands of DNA.
guanine
A base that opposes cystosine within the two strands of DNA.
deoxyribonucleic acid
A variety of nucleic acid and, along with ribonucleic acid, one of two types of molecules that encode genetic information.
lipids
Relatively small macromolecules that span the membrane of
every cell. Most membrane lipids contain phosphate and are
called phospholipids.
enzymes
Proteins that serve to break down complete nutrients into
smaller, useful molecules according to the energy requirements of each cell.
macromolecules
Large types of molecules found in numbers of 1 to 100,000
copies per cell. Macromolecules include proteins, polysaccharides, nucleic acids, and lipids.
messenger RNA
A single-strand structure that contains the sugar ribose and
uridine (U) in place of the thymidine present in DNA. Messenger RNA is used as the actual template for protein synthesis.
proteins
Macromolecules that comprise 100 to 600 amino acid residues.
The majority of proteins are enzymes.
nonpolar
A molecule in which there is no charge differential between each
end.
ribonucleic acid
A variety of nucleic acid and, along with deoxyribonucleic acid, one of two types of molecules that encode genetic information.
nucleic acid
A macromolecule consisting of a sugar-phosphate repeating
structure that is usually large and can be millions of units long.
Each sugar has one of four possible basic molecules, called bases or nucleotides, attached.
sterols
A type of lipid useful as targets for antibiotic therapy of fungi.
polar
A molecule in which there is a positive charge at one end and a
negative charge at the other.
thymidine
A base that opposes adenine (A) within the two strands of DNA.
polysaccharides
Macromolecules in which sugars are polymerized into long
chains. Polysaccharides provide strength to microbial cells to keep them from breaking open.
translation
The process of protein synthesis.
uridine
A material found in messenger RNA, as opposed to the
thymidine that exists in DNA.
cell envelope
All the covering layers of a bacterium, including the cytoplasmic membrane and cell wall.
active transport
A pumping mechanism that runs on the cell’s energy resources
and uses protein transporters in the membrane to bring desirable
chemicals into the cell.
cell wall
A layer of the cell outside the cell membrane that confers rigidity and shape.
basal body
Two to four rings mounted on a rod; they secure the flagellum to
the cell envelope.
chemotaxis
A process in which bacterium moves toward or away from
chemicals.
bacillus
A common morphology of bacteria composed of a rod-shaped cell.
coccus
A common morphology of bacteria composed of a spherical shaped cell.
capsule
A covering, usually a polysaccharide, of the whole cell that makes the cell slippery, preventing white blood cells from
capturing it and antibodies from binding to it.
colony
A visible clump of cells; the colony’s color and appearance are often helpful in eliminating possibilities to assist in identification.
cytoplasm
The content within the cytoplasmic membrane.
fimbriae
Small, hairlike appendages present on the external surface of many bacteria and usually seen in hundreds per cell. Fimbriae specifically refer to “attachment factors” (or “holdfasts”) that attach to host cells.
cytoplasmic membrane
A boundary structure present in all living cells that defines inside
and outside; is also called the cell membrane or plasma
membrane.
flagella
Hairlike appendages that allow bacteria to attach to sites for the
purpose of growth and motility functions.
endospores
Thick spore structures that grow inside cells and are therefore
protected from heat, drying, freezing, and harsh living
conditions.
flagellin
Corkscrew-shaped polymerized proteins present in filament that
are normally several times longer than the entire bacterial cell.
endotoxin
Another name for lipid A; a potent inducer of inflammatory
reactions.
glycocalyx
Another name for capsule or sugar coat.
filament
The major part of a flagellum that contains long, helical
structures made of the polymerized protein flagellin.
Gram’s stain
The microscopic staining procedure discovered by Hans
Christian Gram used to differentiate between gram-positive and
gram-negative bacteria. The four steps of Gram’s staining are:
Stain with the primary stain, crystal violet; fix the crystal violet
with Gram’s iodine so that it aggregates; wash the aggregates
from the porous gram-negative bacteria with acetone-alcohol;
and counterstain with safranin to make the gram-negative cells
readily visible.
gram-negative
Bacteria with three-layered cell walls.
lipopolysaccharide
A material that composes the outer membrane of three-layered
gram-negative bacterial cells.
gram-positive
Bacteria with two-layered cell envelopes.
lysis
A process in which bacteria with damaged cell walls explode due to increased internal osmotic pressure.
granules
Polysaccharides or polyphosphates in the cytoplasm that usually
provide an energy source and are available when the cell has a
special energy need; also called inclusions.
organelles
Membrane-bound sacks that are smaller than a cell.
hook
A flexible piece at the proximal end of filament that can bend to
function as a universal joint.
peptidoglycan
A polysaccharide called glycan that is cross-linked to other
polysaccharide molecules by short peptide cross-bridges to form
a fishnet-like structure.
lipid
A The proximal end in the outer half of the membrane on gramnegative
bacteria that anchors it to the cell.
pili
Small, hairlike appendages present on the external surface of many bacteria.
plasmids
Small pieces of DNA that normally contain only a few genes,
often for highly specialized functions.
spirochete
A common morphology of bacteria composed of a helicalshaped
cell.
proteinaceous flagella
The organelle of motility present in many bacteria.
spores
The most stable form of life, spores are wrapped in multiple
layers of peptidoglycan and protein; there may also be other
polysaccharide layers. Unlike vegetative (growing) cells, spores contain very little water.
random-based walk
A process in which bacteria try to move randomly in different
directions and only go a significant distance when the result is
favorable to them.
vibrio
Short spirochetes that contain less than a full helical turn or are
comma shaped.
ribosomes
Enzymes that perform translation; ribosomes include bacteria and eukaryotes.
sex pilus
Small, hairlike appendages on the external surface of bacteria;
normally associated with gene transfer. A given cell usually has
only one or two sex pili.
bulk transport
A type of transport found in eukaryotes that uses endocytosis or
exocytosis to acquire nutrients and secrete waste products by
creating a vesicle.
cell receptor
A structure on the outside of a cell that binds to a ligand.
ligand
The general term for any type of molecule a receptor binds to.
endocytosis
A process through which a cell engulfs a large molecule to
acquire nutrients.
lysosomes
Organelles filled with toxic chemicals and degradative enzymes
that digest vesicle contents during phagocytosis.
endoplasmic
reticulum
A component within an organelle that translates proteins.
mitochondria
A component within an organelle that produces energy.
exocytosis
A process through which a cell secretes whole antibody
molecules to remove waste products.
nuclei
The DNA-containing defining characteristic of a eukaryote.
Golgi apparatus
A component within an organelle that packages materials to be
secreted through exocytosis.
phagocytes
Specialized groups of white blood cells that travel to all parts of the body to clean up problems.
phagocytosis
A form of cell-eating ndocytosis; useful for ridding the cell of
debris.
chitin
The polysaccharide that composes the cell walls of most fungi.
pseudopodia
Meaning “false foot,” a portion of the cell that extends to engulf
unwanted material during the process of phagocytosis
heterotrophic
A type of fungi that uses organic material made by other cells.
vacuole
A component for food or storage within an organelle.
hyphae
In molds, long chains of hairlike connected cells; can be divided
into two classes: septate and aseptate.
vesicle
A small, membrane-bound sac formed when a cell receptor binds
to a ligand, invaginates into the cell, and pinches off to contain
the ligand.
mycelia
Fuzzy masses of hyphae.
aseptate
A class of hyphae that lacks cross-walls.
saprobes
A type of fungi that obtains nutrients from dead organic material.
septate
A class of hyphae that contains cross-walls separating individual
cells.
ATP
Adenosine triphosphate, the cell’s energy storage chemical.
symbiotic
A type of fungi that obtains nutrients from other living cells
without harming them.
cellular slime mold
A type of slime mold that grows as a group of individual cells.
acellular slime mold
A type of slime mold that forms into a plasmodium.
chlorophyll
A material that uses energy from sunlight to convert carbon
dioxide and water into carbohydrates and oxygen. Chlorophyll
captures photons of light and transfers the energy to
mitochondria that, in turn, produce ATP.
algae
A unicellular protist structure; sometimes grows in large groups
as kelps and seaweeds.
chloroplasts
Organelles that contain chlorophyll.
amoebas
A type of protozoan; amoebas are pseudopodia and move by
crawling.
ciliates
A type of protozoan that uses its organelles of motility for
locomotion and food gathering through cilia that beat in a
coordinated manner.
cyst
The resting, or dormant form, of a protozoan during its lifetime.
plasmodium
A collection of cells that are fused together.
diatoms
Algae that produce a silicon structural matrix that settles to the bottom of the ocean when the organisms die.
protists
A broad grouping of eukaryotes other than plants, animals, and
fungi. The kingdom Protista includes algae, protozoa, and slime molds; protists usually have rigid cell walls
flagellates A
type of protozoan that uses its organelles of motility for
locomotion and food gathering.
protozoans
Unicellular protists that lack photosynthetic ability; can be
identified microscopically by locomotion apparatus, general
shape and size, number of nuclei, and presence of cyst forms.
photosynthesis
The process of using energy from sunlight to convert carbon
dioxide and water into carbohydrates.
slime mold .
Protist molds that produce spores and usually grow in fungi
habitats. They are not considered fungi; several slime molds
have flagella or pseudopodia, whereas all fungi are nonmotile
phytoplankton
Oxygen-producing, free-floating masses found in the world’s
saline waters; the basis for the marine food chain.
sporozoite
An infectious form produced by sporozoa, a type of protozoan
with no appendages.
trophozoite
The vegetative, or growing form, of a protozoan during its
lifetime.
capsid
The protein coat surrounding the nucleic acid genome inside a virus.
vectors
Carriers of pathogens in disease transmission.
capsomere
The protein subunit of a capsid.
adsorption
The process by which a virion attaches to a host cell.
carcinogenic
Describes things that cause cancer.
attachment factor
Protein on the surface of a virion that attaches to specific receptors
on the surfaces of host cells.
cell killing
Instances where cells are killed by viruses in an area.
bacteriophage
Bacterial viruses; called as such because they cause a hole in a layer
of bacteria in a petri dish by killing the bacteria.
cytopathic effects
Changes in human cells caused by viral infection.
enveloped virus
A virus coated with an envelope.
lyse
Refers to the breaking open of cells, as when lytic viruses break cells open.
glycoprotein
A protein with a carbohydrate attached.
lysogens
Viruses that can lyse, or break open cells.
host factory
Organisms required by viruses to supply the enzymes and building
blocks necessary to replicate.
naked virus
A virus without an envelope.
inclusion bodies
Microscopically observable dark areas of virus particles.
nucleocapsid
The nucleic acid and its capsid taken as a unit.
leukemias
Cancers in cells that move throughout the body freely; usually occur in white blood cells.
obligate intracellular parasites
Organisms incapable of growing outside of a host cell.
plaque
An area with no living cells.
round up .
When viral host cells no longer adhere tightly to the bottom of the
tissue culture dish
provirus
Viruses that can lyse, or break open cells.
syncytia formation
A process wherein cells are caused by viruses to fuse together into giant cells.
receptor
Surface features on potential host cells to which virions attach.
transformation
A process wherein tumor viruses cause the cells to keep growing until piles of cells are visible in the dish; the same mechanism causes cells of a tumor to grow uncontrollably or metastasize.
retrovirus
Viruses that carry out transcription in reverse.
tumor
A solid or tissue cancer.
reverse transcriptase
DNA polymerase that reverses the normal transcription process by transcribing RNA into DNA.
tumorigenesis
The formation of tumors.
virions
Complete virus particles.
virus .
The simplest life-form on earth; classified as non-living because
they cannot replicate independent of other organisms
virus particle
Any virus with its appropriate coating layers.
Creutzfeldt-Jacob disease
Spongiform encephalopathy in humans.
Kuru
Another name for spongiform encephalopathy in humans.
acidophiles
Bacteria that grow in acidic environments.
prions
The smallest known replicating agents; they do not have DNA,
RNA, or nucleic acids.
aerobes
Bacteria that grow in the presence of oxygen.
scrapie
Spongiform encephalopathy in sheep.
alkalophiles
Bacteria that grow in alkaline environments.
spongiform encephalopathy
A condition caused by prions, named for the sponge-like appearance it creates in the brain.
anaerobes
Bacteria that grow only in the absence of oxygen.
transmissible spongiform
encephalopathy
The full name of spongiform encephalopathy, referring to its
transmissible nature.
antagonism
A mutually harmful relationship between organisms.
aseptic techniques
Techniques used to avoid contamination when working with
bacteria.
Brownian motion
The process by which molecules in a solution are always bouncing around and off of one another.
autotrophs
Bacteria (and other organisms) that can use carbon dioxide from
the air as a source of carbon.
chemoautotrophs
Bacteria that do not require either sunlight or organic nutrients, but rather use minerals and gases from the air, and derive their energy from chemicals found in rocks.
auxotrophs
Bacteria with mutations that disallow them from making a given
vitamin.
commensalism
A form of symbiosis where one organism helps another, but the
first organism is unaffected either for good or bad by the second.
blood agar
A medium generally used for the isolation of human pathogens
from body sites such as the throat.
complex (nonsynthetic) media
Media used in bacterial culture whose chemical composition is not completely known.
broths
Liquid media used to grow bacteria.
defined (synthetic) media
Media used in bacterial culture with completely known chemicals.
differential media
Media that allow multiple types of bacteria to grow but
differentiate them such that they can be identified.
fastidious organisms
Organisms that require vitamins or similar nutrients.
diffusion
Spreading out.
halophiles
Bacteria specially adapted to growth in high-salt conditions.
enriched medium
Media used in bacterial culture with particular nutrients added to
help the bacteria grow.
heterotrophs
Bacteria (and other organisms) that require their carbon source to already be in an organic form, such as a sugar or amino acid.
extreme thermophiles
Bacteria that have been found growing at boiling temperature and
even above.
mesophiles
Bacteria that grow best at warm temperatures.
facultative anaerobes
Bacteria that grow with or without oxygen.
methanogens
Bacteria that derive their energy from carbon dioxide and
hydrogen to produce methane gas.
microaerophiles
Bacteria that require reduced levels of oxygen to grow.
osmotic (hydrostatic) pressure
Pressure caused by water attempting to move through a membrane by osmosis.
mutualistic symbiosis
Symbiosis wherein the organisms need each other for a high quality of living.
parasitism
A symbiotic relationship that is beneficial to one organism and
harmful to the other.
normal flora
Organisms that usually inhabit a given habitat and are not harmful.
petri dish
Small, usually plastic dishes used in cultures.
obligate aerobes
Bacteria that require the presence of oxygen to grow.
photoautotrophs
Photosynthetic bacteria that can use the energy in light, as plants
do, to produce their own energy.
obligate halophiles
Bacteria that require a high salt concentration to grow.
psychrophiles
Bacteria that grow best at cold temperatures.
selective media
Media that select for certain kinds of bacteria by allowing them to grow while inhibiting the growth of other kinds of bacteria.
symbiosis
Bacteria (or other organisms) that grow together in a community.
synergism organisms'
Symbiosis where the total growth success of the community of organisms is greater than the success would have been individually.
thermoduric bacterium
A bacterium that cannot grow at high temperatures but will not be
killed by exposure to such temperatures over a short period of time.
thermophiles
Bacteria that grow best at hot temperatures.
aliquots
Small samples of a culture.
anabolism
The use of the energy and building blocks left by catabolism to
produce new cellular materials, such as macromolecules.
cell division
The process in which cells divide and form two progeny cells that are equal to the original cell.
anaerobic respiration
Respiration utilizing nitrate or sulfate as the final electron acceptor, rather than oxygen.
chemosynthetic metabolism
The use of salts found in rock as an energy source; employed by some bacteria.
autolytic
Bacteria that produce enzymes that cause their own lysis or break down at room temperature.
colonies
Piles of cells.
binary fission
The process in which cells divide and form two progeny cells that are equal to the original cell.
colony forming unit
A single diluted cell that represents viable bacterial cells, or those cells that could grow and form a colony.
catabolism
The breakdown of complex materials into building blocks or energy that the cell can utilize for synthesis, making more cellular chemicals.
death phase
The period after the stationary phase wherein cells are not receiving sufficient energy or nutrients to maintain viability; also called the decline phase
decline phase
The period after the stationary phase wherein cells are not receiving sufficient energy or nutrients to maintain viability; also called the death phase
feedback inhibition
When the presence of ample serine signals the cell to save energy by not synthesizing more; also called feedback regulation.
denature
The unfolding of a protein or nucleic acid.
fermentation
The production of any product except carbon dioxide or water from catabolism; originally referred to the process of incomplete catabolism of sugars to produce alcohol in wines.
dilution
Introduction of a solvent, usually water, to a solution.
generation
Each division or doubling of a cell.
electron transport chain
A series of carriers in the cell membrane that use electron-derived energy to pump protons out of the cell, creating a gradient.
glycolysis
A process wherein glucose is transported to the inside of a cell and
oxidized
exponential growth
When bacteria double in number once every constant unit of time.
glycolysis
A process wherein glucose is transported to the inside of a cell and oxidized
Krebs cycle
The process wherein pyruvate is further disassembled, using oxygen to degrade the carbon completely to carbon dioxide, water, ATP, and energy-containing electrons that are passed on to the electron
transport chain.
product
The chemical produced by a chemical reaction.
lag phase
The period when bacteria do not immediately multiply after they
have just been picked from a petri dish and placed into fresh broth.
pyruvate
The product of glycolysis.
log phase
The period after the lag phase wherein the cells begin to multiply.
reactants
Chemicals involved in a chemical reaction.
metabolism
All of the chemical processes that occur in a cell.
reaction
A chemical process that consistently leads to a chemical change.
oxidative phosphorylation
The transfer of electrons to oxygen coupled with the synthesis of ATP.
respiration
The passage of electrons to oxygen to produce water.
stationary phase
The period after the log phase wherein cells maintain their cell
number but are not able to produce new cells, or they are dying and producing new cells at about the same rate
cistrons
Individual genes in an operon.
substrates
Chemicals involved in a chemical reaction.
coupling
This simultaneous synthesis of RNA and protein.
total cell count
The number of cell colonies in a cell sample multiplied by the
dilution factor.
metabolic pathway
The series of enzymes needed to complete a task and produce an end product, such as an amino acid.
turbidity
How turbid a culture is; one way of measuring the number of cells in a culture.
operon
A cotranscribed gene cluster.
anticodon
The transfer RNA binding site for the codon.
pathway
A set of genes used for a complete task.
polysomes
Multiple ribosomes held together by the mRNA thread; indicative of very active protein synthesis.
translation
The process of translation from mRNA into amino acid chains.
ribosomal
RNA Translates mRNA into amino acid chains.
triplet
Three ribonucleotides in a row; one codon.
RNA polymerase
The enzyme responsible for transcription; formally, DNA-dependent RNA polymerase.
base pair
Two pairs of nucleotides (A and T, C and G) that always align with each other on connected DNA strands.
transcription
Transcription of a DNA molecule into a messenger RNA molecule.
bidirectional
Refers to the fact that DNA synthesis proceeds in both directions from the point of origin.
transfer
RNA Bring amino acids to the appropriate site for addition during protein elongation.
chromosome
A very large circular molecule of several million base pairs of DNA.
complementary
Refers to the structure of DNA, which has nucleotides on one strand that match up with specific nucleotides on the other strand.
diploid
Describes organisms, such as eukaryotes, with two copies of each chromosome.
DNase
An enzyme that degrades DNA.
gene therapy
The treatment of disease by introducing genes into a human or other organism.
genetic engineering
The overall processes of changing the normal genetic character of an individual or providing new gene products.
genetics
The study of heredity.
genome
The collection of all the genes in a cell.
proofread
Task performed by DNA polymerase on new nucleotides to ensure polymerase that any A is opposite a T in the template, and any G is opposite C.
haploid
Describes organisms, such as prokaryotes, with one copy of each chromosome.
proteinase (or protease)
An enzyme that degrades protein.
heredity
How genes are passed from one generation to the next.
recombinant DNA technology
A series of tools, enzymes, and bacterial hosts that allow researchers to isolate and identify the mutant adenine deaminase gene.
mutant
An organism with a sudden change in its DNA.
replication
The enzymatic process of duplicating a genome.
origin of replication
The discrete site on a chromosome that signals to the enzymes the proper location to begin replication.
RNase
An enzyme that degrades RNA.
transfection
When a virus is used to carry foreign DNA into another organism.
viral vectors
Viruses used in gene therapy
transforming principle
The observation, first made by Frederick Griggith, that genes can functionally affect the character of cells, and that genes can be transferred from one cell to another.
wild-type
bacterium
A strain of Streptococcus pneumoniae with which microbiologist Frederick Griffith experimented in the 1930s; used to discover and demonstrate the transforming principle.
RNase
An enzyme that degrades RNA.
transfection
When a virus is used to carry foreign DNA into another organism.
viral vectors
Viruses used in gene therapy
transforming principle
The observation, first made by Frederick Griggith, that genes can functionally affect the character of cells, and that genes can be transferred from one cell to another.
wild-type
bacterium
A strain of Streptococcus pneumoniae with which microbiologist Frederick Griffith experimented in the 1930s; used to discover and demonstrate the transforming principle.
active repressor complex
The active combination of an aporepressor and a
corepressor.
aporepressor
An inactive repressor protein.
inducible genes
Genes that are usually not expressed unless an ppropriate energy source is available in the environment.
corepressor
A protein that causes repression by activating an aporepressor.
induction
The process by which an inducible gene is activated and expressed.
feedback inhibition
Refers to instances where an end product inhibits expression of its own pathway.
lac operon
An inducible gene in E. coli that requires lactose for expression.
gene expression
The process by which the information encoded in a gene is made into a functioning, observable protein or other component of the
body.
operator
A binding site on DNA that helps to regulate the expression of a
given gene through interactions with promoters and repressors.
inducer
A molecule that begins gene expression, such as a source of energy that activates an inducible gene.
promoter
A DNA segment that regulates the expression of a given gene.
repressible systems
Systems that can be turned off at the transcriptional level when it is advantageous to the cell.
frame-shift deletions
A mutation involving the loss of numbers of amino acids not
divisible by three that cause the following amino acids to shift back, garbling the rest of the chain.
repressor
A protein that regulates the expression of a given gene.
genotype
The genetic sequence of a cell.
Ames test
A test developed by Dr. Bruce Ames to identify which chemicals cause mutation.
genotypic changes
.
Refers to changes in a particular, known gene.
carcinogens
Chemicals capable of causing mutations that lead to cancer.
heritable
Describes genetic information or other traits that can be passed down from one generation to the next.
constitutive system
Describes a system that is mutationally always turned on and cannot be turned off.
induced mutations
Mutations caused by man-made mutagens.
in-frame deletions
Mutations involving the deletion of numbers of amino acids
divisible by three.
nonsense mutations
Mutations resulting in an early stop codon.
insertions
Mutations involving the insertion of amino acids.
phenotype
Physical characteristics.
lactose auxotroph
A cell that can no longer utilize lactose.
regulatory mutations
Mutational control occurring outside of the affected structural genes.
mutagens
Chemicals and other factors not normally found in nature that alter DNA sequences.
spontaneous mutations
Mutations that occur by mistakes in DNA synthesis or by exposure to ultraviolet rays.
mutations
Changes in DNA sequence.
structural genes
Gene sequences that code for actual proteins.
substitution mutations
When one or more nucleotides are erroneously replaced by one or more other nucleotides.
competent bacteria
Bacteria equipped with the necessary transport proteins for
transformation.
conjugation
Direct transfer of DNA from one bacterium to another.
F+ cells
Cells carrying an F-factor.
F− cells
Cells lacking the F-factor.
F-factor
A plasmid that codes for the pilus and other genes needed for DNA copy and transfer in conjugation; short for “fertility factor.”
generalized transduction
Describes transduction by phages that, having absorbed the entire bacterial chromosome of a host cell, can transfer any gene from the donor bacterium.
high frequency of recombination
Occurs when the F-factor integrates into the donor bacterial chromosome; may transmit the entire donor chromosome and finally
the integrated F-factor sequences if attached long enough.
transformation
Bacterial gene transfer wherein the bacteria are transformed into a different genotype.
pilus tip
An attachment site or ligand for specific receptors on bacteria that lack an F-factor.
aciduric bacteria
Bacteria, such as Helicobacter pylori, that are resistant to acid.
specialized transduction
Describes transduction by phages that always pick up just one area of the donor bacterial chromosome and can therefore transduce a limited number of bacterial genes.
antiseptics
Milder disinfectants that tend to be used on human flesh.
transducing particles
Particles that contain bacterial DNA rather than phage DNA; may later transfer this DNA into the DNA of another bacterium.
aseptic
Without contamination.
transduction
A bacterial gene transfer mechanism in which a phage carries one or more genes from one bacterium to another.
autoclave
Essentially a large pressure-cooker used to heat solutions beyond the boiling point for purposes of sanitization.
bactericides
Disinfectants that show preferential killing of bacteria.
disinfection
A reduction in the number of viable microbial organisms in an
area.
bacteriostatic agents
Disinfectants that inhibit the growth of bacteria but do not kill.
flash pasteurization
A process of pasteurization at 71.5oC for fifteen seconds.
biocides
A nonspecific disinfecting agent.
fungicides
Disinfectants that show preferential killing for fungi.
cationic detergents
A disinfectant that kills microbes by dissolving membrane lipids.
fungistatic agents
Disinfectants that inhibit the growth of fungi but do not kill.
chemiclaves
Devices that use harsh chemicals such as ethylene oxide or gamma irradiation to achieve sterilization.
halides
A category containing, among other chemicals, iodine and
chlorine, two bactericidal agents.
iatrogenic disease
A disease induced in a patient by a physician, perhaps due to a
failure to properly sterilize.
phenol coefficient
The effectiveness of a disinfectant agent divided by the
effectiveness of phenol; a measure used to describe the
effectiveness of a given disinfectant.
incineration
A method of sterilizing metal by burning it.
phenolics
Milder derivatives of phenol.
nosocomial diseases
Diseases acquired in the hospital setting.
resident organisms
Organisms at their normal site of growth or niche.
pasteurization
A process that heats foods, such as milk, to a high enough
temperature to kill most vegetative cells; usually achieved by thirty minutes at 63oC.
sanitize
To treat something in such a way as to reduce microbes to a safe level.
phenol
A chemical that has been used in diluted forms to cleanse hands
before surgery; called the gold standard of disinfectants.
sterilization
A way of killing all microbial life on an object.
transient organisms
Organisms that are not at their normal site of growth or niche.
ultrafiltration
Filtration for microbes using a filter with pore sizes smaller than
the smallest bacterium.
ultrapasteurization
A process of pasteurization at 82oC for three seconds.
virucides
Disinfectants that show preferential killing for viruses.
aminoglycosides
Antibioitics that cause bacteria to incorrectly read codons.
ampicillin
A broad range derivative of penicillin whose modification allows it to penetrate the outer membrane of gram-negative bacteria and kill
them.
antibiotic
susceptibility
The extent to which an organism is susceptible or resistant to the
various antibiotics.
chloramphenicol
Antibacterials that inhibit the formation of peptide bonds.
antibiotics
A completely new class of chemical agents that can kill or inhibit microbes without harming a human patient; literally “antilife
compounds.”
ciprofloxacin
A kind of polymixin that is tolerated quite well by human
membranes and therefore used internally and extensively.
β-lactam
A four-membered ring structure in penicillins that is crucial to their activity.
erythromycin
Antibacterials that inhibit movement of the peptidyl-tRNA to prevent addition of more amino acids.
broad-spectrum antibiotics
Antibiotics that can inhibit most all organisms.
Kirby-Bauer test
A major test of antibiotic susceptibility in organisms.
chemotherapeutic agents
Various chemicals that can be used broadly to kill infectious agents; most commonly associated with agents used for the treatment of cancer today.
minimum effective therapeutic dose
The most dilute concentration of antibiotic required to inhibit
bacteria growth in a specific patient.
minimum inhibitory concentration
The most dilute concentration that inhibits bacterial growth in a
tube dilution test.
selection
In this context, the process wherein mutant bacteria survive and grow in spite of antibiotics, and thus are
considered “selected” to
survive.
narrow spectrum
Antibiotics that inhibit only a specific type of bacteria, such as penicillin, which inhibits only gram-positive bacteria.
selective toxicity
A theoretical ideal for drugs wherein they have 100 percent
lethality for microbes without any ill effects on human patients.
polymyxin
Antibiotics that interfere with membrane transport and are used against gram-negative organisms; usually used topically because of
toxicity to human membranes
selectivity
The degree to which a drug can kill undesirable organisms without harming the patient.
quinolines
Antibiotics that act against bacterial DNA synthesis.
sulfa
Drugs that inhibit the synthesis of the vitamin folic acid from paraaminobenzoic
acid.
rifampin .
An antibiotic that inhibits bacterial RNA synthesis
tetracyclines
Antibacterials that inhibit tRNA binding.
therapeutic index
The lowest toxic dose of an antibiotic divided by the minimum
effective therapeutic dose; tells us the range of dosage we can use in the human body.
aerosols
Droplets produced by coughing or sneezing; a common mode of
microbe transmission.
tube dilution test
A test in which the antibiotic is serially diluted into several tubes of bacteria to determine how little antibiotic is required to stop
bacterial growth
asymptomatic infection
Infections that do not manifest symptoms even though the microbe is
present and normally growing; also called a subclinical or inapparent
infection.
zone of inhibition
The area of dead or growth-inhibited organisms left by an antibiotic in a Kirby-Bauer test of antibiotic susceptibility.
bacteremia
Bacteria in the blood.
abscesses
Walled off, discrete infections to which the cells of the immune
system cannot gain entry.
chronic carrier
A person who sheds a given microbe during its latent state and can therefore spread the disease though he is asymptomatic himself.
acute infection
An infection that begins abruptly, usually with severe effects.
chronic infection
An infection that appears insidiously and lasts for extended periods.
clinical disease
A disease with visible symptoms.
epidemic
An outbreak of a disease in a restricted area such as a city or state.
communicable diseases
Diseases whose agent can be passed from one host to another.
epidemiology
The practice of identifying new organisms and their mode of spread.
contagious disease
A highly communicable disease.
exoenzymes
Enzymes secreted by organisms.
endemic
An adjective describing diseases that take place within a specific
locale.
exotoxins
A toxin secreted from the microbe and a common virulence factor.
endotoxins
An integral part of the microbe that is a common virulence factor.
extracellular pathogen
A pathogen that survives in humans by characteristic virulence factors that allow it to evade phagocytic cells that would otherwise destroy it.
fecal-oral route
A route of transmission caused by bacteria moving from fecal matter to a host's mouth; for instance, this may occur if a restaurant worker fails to wash his hands after using the restroom.
infection control committee
Committees at local hospitals responsible for identifying and
controlling the spread of outbreaks as rapidly as possible.
fomite
An inanimate object through which an infection spreads.
infection control nurse
A nurse responsible for identifying and controlling the spread of outbreaks as rapidly as possible.
hemolysins
Toxins or enzymes that cause red blood cells to lyse and release their contents, which then become available to the pathogen as nutrient
sources.
infectious dose
Refers to how many organisms are required, on average, to establish an infection.
horizontal transmission
Transmission of a disease from one individual to another.
intracellular pathogen
A pathogen that has developed virulence factors that allow it to
survive even inside of phagocytic cells.
inapparent infection
Infections that do not manifest symptoms even though the microbe is present and normally growing; also called an asymptomatic or subclinical infection
latency
The extent to which a disease appears to subside when in fact the patient continues to host the microbes in a dormant state.
latent state
A phase during which symptoms of a disease subside
and the patient is apparently well, but somewhere in the body the microbes carry on in a dormant state.
nonvirulent microbes
Microbes that do not cause disease.
leukocytosis
Increased numbers of white blood cells.
Opportunistic infections
Diseases caused by nonpathogenic organisms such as normal flora.
leukopenia
Reduced numbers of white blood cells.
pandemic
A disease that spreads over the entire world.
local infection
An infection restricted to a specific area.
portal of entry
The site where pathogens gain access to tissue that can be infected.
locale (focus)
A location from which an infection spreads.
primary (frank) pathogens
Pathogens that can successfully invade and infect healthy hosts.
primary infection
Infection caused by the organism that initiated the infection.
subclinical infection
Infections that do not manifest symptoms even though the microbe is present and normally growing; also called an asymptomatic or inapparent infection.
secondary infection
A second infection that was led to by the primary infection but
which is caused by a second microbe.
systemic infection
An infection spread via the blood or lymphatic systems.
septicemia
Actively growing bacteria in the blood.
toxemia
An infection caused by toxins spread through the bloodstream.
sequelae
Diseases that seem to completely mend but have specific aftermaths
or follow-up problems later.
vertical transmission
Transmission of a disease from parent to progeny.
subacute infection
An infection of intermediate duration and severity.
viremia
A virus in the blood.
virulence factors
The microbial chemical factors that are required for or important in establishing disease.
acquired immunity
Involves induction of a specific immune response that is
remembered, which provides for long-term immunity.
alternative pathway
A pathway of the complement system beginning with C3 that is
believed to be very important in preventing infections before
antibody production has time to occur.
classical pathway
The first component, C1, binds to bacterial-bound antibodies and becomes activated so that it causes binding and activation of other components, C4, C2, C3, and C5, in that order.
alveolar macrophages
Leukocytes, or white blood cells, in the lungs.
complement
A special set of proteins that circulates throughout the body and binds to bacteria.
basophils
The principle nonphagocytic cells of natural immunity.
complement cascade
A process in which complement circulates throughout the body and binds to bacteria, called as such because the proteins act in a sequential order.
chemotactic factors
Factors created by the classical pathway that recruit (or attract)
phagocytic cells to the site of infection.
cytokines
Small chemicals secreted by one cell as a form of communication or
signaling to other cells.
ciliated epithelial cells
Natural barriers to infection that sweep the mucous layer toward
bodily orifices.
diapedesis
Phagocytes’ process of exiting the blood stream and squeezing
between vascular endothelial cells.
eosinophils
Principle nonphagocytic cells of natural immunity.
leukocytes
White blood cells.
granules
In this context, components of eosinophilis and basophils cells
containing histamine and various toxic chemicals
macrophages
A type of white blood cell comprising about 8 percent of the average count, appearing in many tissues such as lung, liver, and kin cells.
immunity
Human or animal systems of defense to fight off infection.
mast cells
Cells that are found in the tissues and appear to have identical functions to those of basophils.
interferons
Small proteins released by infected macrophages, fibroblasts, and T cells to alert neighboring cells
membrane
attack complex
A complex that forms a pore in the bacterial membrane, resulting in leakage, lysis, and death of the microbe.
iron-binding proteins
Proteins that sequester iron to prevent adequate nutritional
availability for microbes.
natural immunity
Immune functions, sometimes called nonspecific resistance factors, including things that are innate, or already present in the body.
neutrophils
Cells whose nuclei stain with a neutral dye.
opsonin
Another name for C3b, which includes a specific receptor for
phagocytic PMNs (polymorphonuclear leukocytes) to bind and subsequently ingest opsonized particles.
phagosome
A membrane bag inside phagocytic cells.
PMNs
White blood cells that function to engulf and digest foreign matter; account for 55 percent of all white blood cells.
reticuloendotheli al system
Before the various kinds of phagocytic cells were characterized, the whole system was called by this name.
active immunization
Also called active vaccination, the active prevention of diseases in a potential host; usually provides lifelong immunity.
agglutination
The process wherein antibody molecules cross-link bacteria or
other microbes together so that large aggregates of microbes can be
formed
antibody
(Ab) Proteins used by the body to identify and combat foreign objects and microbes.
allergens
Antigens that induce allergies.
antigenpresenting cell (APC)
An accessory cell necessary for the creation and proliferation of memory cells.
allergic
When one is especially sensitive to specific antigens.
antigens (Ag)
Proteins or polysaccharides used to recognize foreign materials.
anaphylactic hypersensitivity
A Type I hypersensitivity reaction where IgE molecules bound to basophils and mast cells bind allergens, which causes release of
histamine and other potent active chemicals.
atopic
A category of people with high levels of IgE and several resultant allergies.
anaphylactic shock
A reaction to release of histamine throughout the body wherein blood pressure can drop precipitously and death may occur within minutes.
atopic
A category of people with high levels of IgE and several resultant allergies.
B lymphocytes
Antibody-producing cells.
cell-mediated immunity
Immunity conferred by white blood cells, especially T cells.
degranulate
A step in an allergic reaction wherein cells release histamine and other chemicals that cause allergic reactions.
clonal deletion
A process wherein B and T cells are deleted because they recognize themselves as Ags early in a person’s life.
delayed hypersensitivity
Mediated by immune cells; cells must migrate from the blood
stream to the affected tissues before damage is observed, which requires one to two days to develop.
complement fixation
The binding of complement proteins.
epitope
An amino acid recognized by antibodies.
constant region
The part of the antibody amino acid chain that does not change.
fragment antigen binding (Fab)
The portions of the antibody molecule's amino acid chain
containing the antigen binding sites.
cytotoxic T cells (Tc)
T cells that express CD8 protein on the surface; cells kill virally
infected cells and may cause tissue graft rejection.
globulin
A globular, or roundish, protein in the shape of a ball.
haptens
Small chemicals that fit into the antibody-binding site.
immunization
The general process of increasing a specific type of the body’s immune capability to a living or inanimate antigen.
histamine
A chemical involved in triggering allergic reactions.
immunogen
A B cell–stimulating antigen.
humoral immunity
Refers to antibodies that stay in the fluid part of the blood.
immunoglobulin
Antibody proteins as they have been isolated from the blood.
immediate hypersensitivity
Called as such because the IgE antibodies are already bound before Type I hypersensitivity occurs, and it therefore occurs immediately.
inducibility
A hallmark of acquired
immunity, the extent to which contact with foreign material stimulates immunity.
immune complex diseases
Complexes of antibodies and antigens are not digested well, get filtered through the kidney, and cause inflammation; also stick to blood vessels, which causes damage to host tissues when the complexes are ultimately destroyed.
interleukins
A subset of cytokines made by leukocytes.
isoagglutinins
Naturally occurring antibodies.
memory cells
Daughter cells created on the event of B cells binding with
antigens; essentially identical to their parent cells.
lymphocytes .
A subset of leukocytes essential to acquired immunity and
responsible for specifically recognizing foreign antigens
monoclonal antibodies
Large populations of antibodies created from one clone or cell.
major histocompatibility
complex
Receptors that allow immune system cells to recognize each other in the body.
nonself
A classification for foreign antigens employed by immunologists.
mediators
Chemicals, like histamine, released by cell granules and responsible for triggering allergic reactions.
opsonization
The process in which the Fc portion of the antibody changes
configuration such that a specific receptor on the phagocytes binds
them tightly.
memory
A hallmark of acquired immunity, the tendency that subsequent exposure to a given antigen will result in a faster and greater response to the identical foreign material.
passive immunization
A type of immunization, but not vaccination, wherein specific
antibodies are transferred from one individual to another suspected of having recently been exposed to the same microbe.
perforin
A toxic protein secreted by Tc cells that opens channels or holes in infected cells and kills them so these cells discontinue production of microbes.
secondary antibody
An antibody that binds to human antibodies.
plasma cells
Daughter cells created on the event of B cells binding with
antigens; cells start secreting antibodies of the same type that
originally bound the antigen.
self
A classification for our own antigens employed by immunologists.
polyclonal antibodies
A population of antibodies descended from several B cells.
sensitization
The early exposures that lead to IgE binding to cells, causing
sensitivity to a particular allergen to develop.
precipitate
In this context, small Ab-Ag complexes are placed in a centrifuge that spins rapidly to generate centrifugal forces (like a washing machine spinning out water) and precipitates the aggregates at the bottom of the tube.
serum sickness
An immune complex disease whose symptoms include generalized fever and inflammation of blood vessels and organs.
receptors
Surface proteins that allow cells to recognize each other.
specificity
Immunity stimulated by contact with foreign material recognizes
only the stimulatory agent.
T cell receptor A
specific surface receptor on T lymphocytes used to recognize
foreign antigens.
T-independent response
Plasma cells are produced to make antibodies in response to
polysaccharide antigens, but no memory cells are formed and this therefore does not yield long-term immunity.
T helper cells (Th)
proliferation of other immune cells.
A subset of T cells that recognizes specific antigens and causes
tolerance
In this context, refers to the way the immune system learns to
ignore self-antigens.
T lymphocytes
A type of lymphocyte that leaves the bone marrow and travels to
the thymus for maturation.
vaccination
The stimulation of an immune response that protects against a
specific living infectious agent.
T suppressor cells (Ts)
T cells that express CD8 protein on the surface; dampen an immune proliferation response so that it stops when an
adequate level is reached.
variable region
The antigen binding sites on the amino acid chain of an antibody
molecule, which are extremely variable.
T-dependent response
Antibody-secreting plasma cells and memory B cells are both
formed in response to protein antigens.
weal and flare
An allergic reaction causing a local skin lesion that is red, raised, and watery inside.
Western blot
analysis
An accurate method of identifying viral proteins in a host.
acute pharyngitis
Strep sore throat.
alveoli
The tiny air sacs of the lung.
C carbohydrate An antigen in the typical
Streptococcus cell envelope, for which humans usually produce antibodies.
cloaking devices
Structures, such as the hyaluronic acid capsule and the S. aureus antibody coating, that allow bacteria to hide from our immune system.
cold agglutinins
Antibodies induced by Mycoplasma in the patient that are useful for diagnosing pneumonia.
diphtheria
A disease, caused by diphtherotoxin, which inhibits the 80S ribosomes of the host, affects the heart and nervous system, and sometimes causes death.
isoniazid
An antibiotic reserved for TB treatment.
diphtherotoxin
The cause of diphtheria; also called Corynebacterium diphtheriae.
meningitis
An infection on the meningeal covering of the brain and spinal
cavity caused by Strep. agalactiae.
Hib
A capsular polysaccharide vaccine that has been useful against Hemophilus influenzae, though it was T cell– independent.
meningococcus
A name for Neisseria meningitidis commonly used in the clinical setting.
Hib conjugate
A version of the Hib vaccine that induces a memory response in the host's immune system.
menomune
A vaccine that is available for four types of the polysaccharide
capsule of Neisseria
meningitidis, but not type b, the most common type.
immune complexes
Complexes of antibodies and antigens that may form and cause permanent kidney damage due to glomerulonephritis.
MRTB
Stands for Multiply Resistant TB, meaning strains of tuberculosis
with resistance to many antibiotics.
obligate intracellular pathogens
Pathogens like chlamydia that cannot produce their own ATP and must acquire it from a host cell.
Quellung test
A test based on anticapsular antibodies that is used to distinguish the capsular types of Streptococcus pneumoniae.
pertussis
A disease, known as whooping cough, that mainly affects young
children; caused by Bordetella pertussis.
rheumatic fever
Heart valve and joint damage that occurs several weeks after acute pharyngitis because of immune hypersensitivity.
pneumonia
Literally a condition of the lungs; may be caused by bacteria, viruses, parasites, fungi, or even physical particulates such as those found in tobacco smoke.
rusty sputum
Phlegm with blood in it.
pneumovax
A vaccine for bacterial pneumonia containing twenty-three of the most common polysaccharide types for use in the at-risk population.
scarlet fever
A rash caused by an erythrotoxin secreted by some strains of Strep. Pyogenes.
PPD
Purified protein derivative, such as certain tubercular antigens.
streptolysins
Antigenic chemicals that
damage cell membranes, including those of the heart and WBCs.
subacute endocarditis
An infective type of endocarditis, or inflammation of the heart, caused by viridans strep.
tubercles
Hard foci in the lung tissue into which TB organisms are walled off; visible by X-ray.
tuberculosis
An invasion of the lung accompanied by tissue destruction caused by
M. tuberculosis; also called TB.
viridans strep
Refers to a group of streptococci that is not actually a genus; virtually every human carries them, but they only cause problems in
those with heart damage.
adenoids
Lymphoid tissue at the back of the nose; a part of the immune
system.
adenoviruses
Naked, dsDNA-containing viruses for which there are at least fifty serotypes.
congenital rubella syndrome
An infection transmitted from pregnant mothers with the rubella
virus to fetuses, especially during the first trimester, that can cause serious birth defects.
antigenic drift
Mutational change in viruses.
Guillain-Barré syndrome
.
An immune disorder; an extremely rare-occurring effect of the influenza vaccine
antigenic shift
Complete gene change in viruses.
hemagglutinin
A viral surface-protein that attaches the influenza virus to the ciliated epithelial cells in the throat so the virus can enter and kill the cells.
chicken pox
An extremely common and contagious disease caused by
vacirella-zoster virus, which also causes shingles, its recurrent
form.
influenza virus
An extremely common virus that could potentially kill many
people a year, but which rarely does so.
common cold
A common infection caused about half of the time by
rhinoviruses.
iron lungs
Large steel tanks used in the 1950s that some children with
poliovirus were condemned to live in with only their heads
sticking out because the machines were the only devices
available that could provide a pressure change on the chest to
force breathing.
keratoconjunctivitis
Inflammation of the conjunctiva and the cornea of the eye.
neuraminidase
A viral surface-protein that breaks down the protective mucous layer that lines the throat.
Koplik’s spots
Reddish patches with white, salt crystal-like centers; the most
distinctive diagnostic sign of rubeola.
poliovirus
A tiny RNA virus that infects the alimentary canal and invades
neurons in the spinal column, where it causes poliomyelitis.
local epidemic
Outbreaks of disease limited to a given area, like a city or state.
respiratory syncytial virus
A virus that commonly causes a serious infection of the lower
respiratory tract in young children.
measles virus
A normally mild disease that usually causes rubeola, but can
cause pneumonia or encephalitis, which can result in permanent mental retardation, epilepsy, deafness, and death.
Reye’s syndrome
A potentially fatal disease affecting all of the organs; can be caused by giving aspirin to children under seventeen while they have influenza, the chicken pox, or other illnesses.
mumps virus
A virus that causes inflammation of the parotid gland (parotitis);
mild in children, but not adults.
rhinoviruses
A set of viruses with at least 113 serotypes that cause about 50
percent of common cold cases.
rubella virus
The three-day measles, or German measles; not considered a problem to the patient, but can be transmitted from a pregnant woman to her fetus, causing congenital rubella syndrome.
syncytia
Large cytoplasms with many nuclei; formation is induced by the respiratory syncytial virus.
rubeola
A seven-day rash that starts as red spots on the head or trunk and spreads toward the extremities; also called the seven-day measles.
Sabin vaccine
One of two vaccines that have virtually eliminated endogenous
polio from the United States; induces a secretory IgA response in the intestinal tract so that future infections are intercepted enterically and not spread into the feces.
Salk vaccine
One of two vaccines that have virtually eliminated endogenous
polio from the United States; prevents spread of the virus though the bloodstream but does not prevent intestinal growth and fecal shedding.
shingles
The recurrent disease caused by vacirella-zoster virus, which
also causes chicken pox, its primary form.
aflatoxins
Toxins produced by Aspergillus flavus that apparently cause
cancer, especially in the liver where they are degraded.
aseptate hyphae
Hyphae (hair-like fungus threads) without cross-walls.
cryptococcosis
An encapsulated yeast found in pigeon droppings that causes
pneumonia and meningitis; recently renamed Filobasidiella,
though cryptococcosis is still used.
aspergilloma
Fungal balls found in body cavities, often as a result of
aspergillosis.
ergot
A mycotoxin produced by Claviceps purpurea that causes
hallucinations and other brain disturbances.
aspergillosis
A fungal pneumonia.
histoplasmosis
An infection of the lung that can spread to other organs; caused by Histoplasma capsulatum.
blastomycosis
Pulmonary infections caused by Blastomyces dermatitidis.
otomycosis
A fungal ear infection occurring from growth in earwax.
coccidioidomycosis
A disease that is mostly pulmonary and meningeal; caused by Coccidioides immitis from alkaline soils.
phycomycetes
Also called zygomycetes because they reproduce sexually by the formation of zygotes; members of the Mucor and Rhizopus genera associated with disease.
pneumocystosis
The most common secondary infection in AIDS patients; a
pneumonia that directly causes some 50 percent of all AIDS
deaths.
septate hyphae
Hair-like threads of fungus with cross-walls; used to recognize
Aspergillus fumigatus.
thermal dimorphism
The defining feature of dimorphic fungi, which have two
morphologic forms: yeast in the tissue at 37oC and mold in the
environment at cooler temperatures.
bacillary dysentery
A disease characterized by frequent watery stools that contain mucus and blood.
bacteriuria
Bacteria in the urine.
coliform
Rod-shaped bacteria that ferment lactose at the proper temperature.
botulinum toxin
A toxin produced by botulism so potent that detectable growth need not be present for intoxication to result.
cystitis
Inflammation of the bladder.
botulism
A disease occurring when canned foods are ingested that have not been heated thoroughly enough to kill all Clostridium botulinum
spores; produces botulinum toxin.
dysentery
Watery diarrhea with blood and mucus, pain, and fever.
brucellosis
A disease in animals caused by the bacterium Brucella; humans are usually infected while handling animals, their meat, or dairy products.
enterotoxin
A protein toxin released by a microbe in the large intestine.
cholera
A disease caused by the choleragen exotoxin, which is excreted by Vibrio cholerae.
food poisoning
Sickness caused by consumption of food.
gastritis
Inflammation of the stomach.
typhoid fever
A fever that presents with intestinal ulcerations with bloody stools, rose spots, and a stepladder fever; caused by Salmonella typhi, which spreads from symptomatic as well as asymptomatic chronic
carriers.
gastroenteritis
Inflammation of the stomach and intestinal lining.
traveler’s diarrhea
A disease caused by enterotoxins secreted by some strains of E. coli.
intoxication
Disease produced by a toxin.
stepladder fever
A fever that rises and falls each day.
pure toxemia
An organism that can be killed by stomach acid and therefore
requires no antibiotic therapy.
salmonellosis
A less severe form of diarrhea.
rose spots
Skin hemorrhages caused by typhoid fever.
urinary tract infection (UTI)
An infection of the urinary system.
zoonosis A
disease transmitted from an animal to a human.
bilirubin
A partial breakdown product of hemoglobin.
Coxsackie virus
Enterovirus whose twenty-nine strains cause a variety of diseases including aseptic meningitis, herpangina, pleurodynia, and
myocarditis; strain B4 has a strong correlation with diabetes.
jaundice
A hallmark symptom of hepatitis wherein the whites of the eyes and even blood appear yellow, the urine is often dark, and the stool a clay gray.
echovirus
Enterovirus whose thirty-one strains cause diseases including
gastroenteritis, respiratory infections, and meningitis.
hepatitis A
immune globulin
Immunoglobulin
proteins from blood of people who had recovered from hepatitis A infection.
hepatitis
A virus (HAV)
A form of hepatitis spread via uncooked shellfish that acquire
virions in seawater from fecal contamination or food handlers with poor bathroom hygiene.
nfectious hepatitis
Another name for the hepatitis A virus; used because fecal-oral
transmission can spread it easily.
amoebiasis
An amoebic disease most commonly caused by Entamoeba histolytica.
balantidiasis
The only major disease caused by ciliates; caused by Balantidium coli.
giardiasis
A disease common among hikers and other outdoors people in the United States; caused by Giardia lamblia
cryptosporidiosis
A disease resulting in diarrhea for one to two weeks in normal
individuals or a profuse diarrhea in immunocompromised patients
who often die of the disease; caused by Cryptosporidium parvum.
helminths
An extremely common roundworm.
cyclosporiasis
A disease whose symptoms include watery diarrhea, cramps, and vomiting that persist for a month or more; caused by the parasites
Cyclospora cayetanensis.
hookworm
A category of parasites including Ancylostoma duodenale and Necator americanus, which attach to human intestines and cause
anemia by sucking blood.
definitive host
A host in which a parasite reproduces sexually.
intermediate host
A host in which a parasite lives
flukes
Flat, leaf-shaped, single-celled parasites that have complex life
cycles and attach to their hosts by means of suckers; often utilize both intermediate and definitive hosts.
intermediate host
A host in which a parasite lives but does not reproduce sexually.
miracidia
The motile forms of hatched Schistosoma eggs, which swim until they find proper hosts.
swimmer’s itch
An immune reaction, caused by Cerceria, whose symptoms include raised papules on the skin.
pinworm
A more widely known name for Enterobius vermicularis, the most prevalent helminth in children.
trichinosis
Disease caused by Trichinella spiralis when contaminated pork is not thoroughly cooked.
proglottid
A segment of the tapeworm; essentially a uterus.
whipworm
A name referring to Trichuris trichiura, whose long, slender shape resembles a bullwhip.
schistosomiasis
A disease caused by the flukes Schistosoma mansoni, S. japonicum, and S.
haematobium, which have a complicated life cycle and are
fairly common.
scolex
The head of a tapeworm; has a hook or sucker for attachment to
infected tissue.
cervicitis
Cervical inflammation associated with cancer, injury from an external object, and sexually transmitted diseases like gonorrhea.
chancre
Painless ulcer in a patient's genital area that exhibits in the first stage of syphilis.
gonorrhea
A common sexually transmitted disease caused by the bacterium Neisseria gonorrhoeae that generally causes urethritis in men,
cervicitis in women, and progresses in women to an invasive PID about ten percent of the time.
chlamydia
A very common sexually transmitted disease affecting the genitals and/or eye; one of several infections caused by Chlamydia trachomatis.
gummas
A granuloma and the third stage of syphilitic infection
characterized by destruction of soft tissue of the bone, heart, brain, internal viscera, and so on, where few or no organisms are present.
energy parasites
Host cells from which ATP is transported.
inclusion conjunctivitis
Eye infection caused in newborns by Chlamydia trachomatis, called as such because of inclusions (endosomal bags of growing
Chlamydia) seen in the cytoplasm of eye cells; causes inflammation and can be transmitted from an untreated, infected mother to her baby.
general paresis
A general group of mental illnesses, including emotional instability, memory loss, impaired judgment, delusions, hallucinations, loss of
vision, eye damage, and speech defects, that develops about twenty years after syphilis infection.
nongonococcal urethritis
An infection of the urethra that is not caused by gonorrhea, most commonly caused by Chlamydia trachomatis.
gonococcus
Another name for the sexually transmitted disease widely known as gonorrhea
PID
Pelvic inflammatory disease. Can refer to infection of any part of the female reproductive system, and is commonly caused by advanced forms of gonorrhea and chlamydia.
pilin
The protein that comprises pili, which are small appendages that
allow bacteria to attach to each other.
reservoir
A source of a given disease. For instance, humans are the only reservoir for gonorrhea.
salpingitis
A disease caused by Chlamydia trachomatis ascending into the
fallopian tubes, where the bacteria cause scarring that leads to closure of the tubes and sterility of the woman.
syphilis
A sexually transmitted disease caused by Treponema pallidum that can occur in three stages: the development of a chancre, the spread of the disease through the blood stream, and the development of
gummas; about twenty years after infection, a group of mental
illnesses called general paresis develops.
urethritis
Inflammation of the urethra caused by gonorrhea
trachoma
A disease of the eye caused by Chlamydia trachomatis that derives from hypersensitivity reactions due to multiple infections and is the
greatest cause of preventable blindness in the world.
acyclovir
The best drug for treatment of all HSV infections because it helps reduce the severity and length of recurrent infections and is especially useful for painful genital recurrences
cervical carcinomas
A common form of cancer that kills thousands of women every year; caused in many cases by papilloma viruses (also a cause for genital warts) and an additional cofactor, such as smoking.
cofactor
Broadly, a cofactor is a condition that exacerbates another condition.
For example, smoking is a cofactor that can cause cervical
carcinomas in combination with the papilloma virus.
disseminated disease of the
newborn
The normally lethal result of transmission from mothers infected with HSV II to neonates
genital herpes
A sexually transmitted disease usually caused by herpes simplex virus II that causes blisters around the genitals that break, becoming
painful ulcers that can remain for weeks, and can continue to recur for the rest of the infected person's life.
herpes simplex virus II
.
The virus that causes genital herpes; a sexually transmitted organism that primarily causes penile, vulvar, and perianal infections
genital warts
Are generally only benign tumors, but a few types are found in over 95 percent of all cervical carcinomas, which are the cause of thirtyfive
thousand deaths in the United States each year.
candidiasis
A fungal infection commonly known as a “yeast infection,”
frequently caused by the extremely common Candida albicans, that presents with pruritis (itching), vaginal burning, and a white cheeselike
discharge.
trichomoniasis
An infection caused by Trichomonas vaginalis, transmitted mainly by sexual contact; symptoms include vaginitis in females and
urethritis in males.
vulvovaginitis
An inflammation of the vagina and vulva, caused by various
infections.
undulating membrane
A membrane that waves, or undulates, back and forth as the
protozoan of Trichomonas vaginalis swims by means of flagella; serves as a readily recognized identification marker.
yeast infection
A common name for candidiasis.
anthrax
An acute disease caused by Bacillus anthracis, considered a primary candidate for biological warfare because of its survival in nature; its potential for spread of billions of spores easily; the severity of the blood infection that includes hemorrhaging, boils, and bloody diarrhea; and an 80 percent mortality rate when untreated.
catalase
Protects Staphylococcus aureus bacteria from lysosomal reactive oxygen compounds.
gas gangrene
Named in reference to the fact that the bacteria are prolific producers of gas, and the lesions become green and then black as the organism
produces extracellular enzymes that putrefy the tissues and block the blood flow; caused by C. perfringens.
coagulase
Secreted by Staphylococcus aureus, clots the blood near the infected site to form an abscess and effectively walls-off the area from the immune system.
Hansen’s disease
A disease of the skin and neurons caused by Mycobacterium leprae
that causes hypersensitivity to develop in most infected people,
which holds growth of the organisms in check, but also slowly destroys neurons, bone, and skin; more widely known as leprosy
coagulase test
The usual differential test for Staphylococcus aureus, used because only S. aureus can coagulate the clotting factors in plasma.
hemolysin
Produced by Staphylococcus aureus to destroy red blood cells.
debridement
The removal of dead tissue and foreign material.
Lepromatous
leprosy
A disease resulting from leprosy where hypersensitivity does not
develop.
exfoliatin
Produced by some strains of Staphylococcus aureus to cause
desquamation or denuding often seen in newborns; this disease is called scalded skin syndrome.
leprosy
The more widely-known name for Hansen's Disease.
leukocidin
Produced by Staphylococcus aureus to destroy white blood cells.
protein A
A most important virulence factor in Staphylococcus aureus; a surface protein resulting in a bacterium that appears on the surface to
be the host, which prevents acquired immunity from developing and has so far prevented the development of a vaccine.
pyogenic
A word describing any pus-forming disease.
VRE
An acronym for vancomycin-resistant enterococcus, a name created for increasingly common vancomycin-resistant strains of Enterococcus faecalis.
tetanospasmin
A toxin that causes muscle spasms, or tetany, and is observed to cause the jaw muscles to contract intensely—hence the common name lockjaw.
tetany
Muscle spasms, in many cases caused by tetanospasmin.
tetanus .
A disease, caused by Clostridium tetani, that affects the muscles and nerves and is easily prevented with the tetanus toxoid vaccine
gingivostomatitis
The primary disease caused by herpes simplex virus I; consists of oral lesions.
herpes labialis
The recurrent disease caused by herpes simplex virus I; consists of cold sores or fever blisters.
Negri bodies
Black inclusions found in the brain tissue of a brain infected with rabies.
herpes simplex virus (HSV)
Comes in two types, HSV I and HSV II; HSV I causes
gingivostomatitis as the primary disease and herpes labialis in the recurrent disease.
rabies A
common disease in wild animals that targets the nervous system
and is transmitted from host to host by way of bites; once symptoms occur, death is inevitable.
hydrophobia A
reaction of aversion to and fear of water in rabid animals and
humans caused by the fact that when a rabid animal/human tries to swallow, the throat muscles contract in an extremely painful spasm.
recurrence
When a latent virus resurfaces to cause trouble in the host after some period of dormancy.
Kaposi’s sarcoma
A tumor caused by human herpes virus 8; one of the major diseases associated with AIDS.
roseola
A rash caused by human herpes virus 6 occurring mostly in children before age three.
latency
Describes viruses, like the herpes viruses, that a person will harbor for life; they may recur only once, or many times.
smallpox
A disease of vast historical import, responsible for countless deaths and the dramatic collapses of empires and nations alike; recent
concern that a bioterrorist might acquire and use it has led the United States government to stockpile vaccines.
warts
Mostly benign growths caused by the many types of papilloma
viruses.
dermatophytes
Fungi that cause skin diseases.
mycoses
Skin diseases caused by fungi.
ringworm
A disease that presents as round, raised areas with intense itching; caused by Microsporum, Trichophyton, and Epidermophyton.
sporotrichosis
A disease caused by Sporothrix schenckii, which grows on plants, wood, and straw, and infects via puncture wounds in the skin; also called rose thorn disease because a rose thorn is considered an ideal object for transmission.
thrush .
Type of candidiasis that occurs in the mouth and causes small, whiteflecks or patches that appear on oral membranes and resemble mild curd when they grow together
bacteremia
Bacteria in the blood.
bubo
An intensely painful, swollen lymph node that is packed with
immune cells and dying tissue, for which the bubonic plague is
named.
Q fever
A disease with influenza-like symptoms that humans usually acquire from aerosols or contaminated animal fluids, including milk; caused
by Coxiella burnetii, which is closely related to Rickettsia.
bubonic plague
A disease caused by Yersinia pestis that is also called “the Black Death” and killed approximately one third of Europeans in the 1300s; normal bacterial hosts include mice and rats, with fleas transmitting the bacteria to humans.
Rocky Mountain spotted fever
A disease that is caused by Rickettsia rickettsii, bacteria which require cycling between blood-sucking arthropods and mammals; found more commonly in the eastern United States in spite of its
name.
fungemia
Fungi in the blood.
septic shock
Occurs when the agent or toxins cause the infected person’s blood pressure to drop below the level required for normal organ functioning.
Lyme disease A
disease caused by Borrelia burgdorferi, which is transmitted by the Ixodes tick, that appears widely in many animals and causes influenza-like symptoms, progressing eventually to immune complex disease and arthritis that can be debilitating though they are rarely lethal.
septicemia
A condition where an agent or its toxins in the blood cause disease, which normally involves the active growth of microbes in the bloodstream.
pneumonic plague
.
An instance of bubonic plague that is spread from human to human via respiratory aerosols
systemic disease
A disease spread throughout the body.
Toxic shock syndrome (TSS)
The deadly results of a failure to regularly change tampons, leadingto the production of excessive amounts of an exotoxin by some
strains of S. aureus, bacteria that grow in and around tampons.
tularemia
A painful disease also known as rabbit fever that commonly spreads via mucous membranes in people who skin rabbits, though a variety of wild animals carry the disease; caused by Francisella tularensis.
typhus
An epidemic caused by Rickettsia prowazekii and transmitted by the body louse; especially a problem in times or war, famine, or poverty.
viremia
Viruses in the blood.
arbovirus
A virus with some four hundred varieties that spread from birds to humans via mosquito bites.
cytomegalovirus (CMV)
A disease called the fifth human herpes virus that causes 10 percent of infectious mononucleosis; can cause a variety of defects in a
fetus/infant, including mental damage and loss of hearing.
hepatitis
A family of viruses spread by blood and semen that may expand in the future.
Ebola virus
A hemorrhagic fever with a high fatality rate. The natural host for
Ebola virus remains unknown, thus, the disease is difficult to
understand. Several epidemics of Ebola have been observed yearly
in Africa.
infectious mononucleosis
An infection caused by the Epstein-Barr virus that is widely known as mono, and also, because it is spread through saliva, as “the kissing disease.”
Epstein-Barr virus (EBV)
The fourth herpes virus and the cause of 90 percent of infectious
mononucleosis. Children under fifteen are usually asymptomatic;
incidence is high in sixteen- to twenty-year-olds. EBV infects B
lymphocytes, causing their cytoplasms to grow dramatically, and remains latent for the infected person’s life.
Lassa fever
An acute hemorrhagic fever recently recognized in Africa.
hantavirus
A hemorrhagic fever pathogen indigenous to the United States. It was first identified when it caused a number of cases in the
Southwest in 1993. It causes hemorrhaging and respiratory failure.
We now have seen it in over half of the United States. The deer mouse is the primary carrier.
Marburg disease
A hemorrhagic fever related to the Ebola virus that was recently
recognized in Africa.
hemorrhagic fevers
Symptoms of these fevers include fever and bleeding from many body orifices, including the mouth, gums, throat, eyes, ears, and nose. In many cases, internal organs rupture or even liquefy due to viral damage. The viruses come in many shapes and sizes; RNA or DNA, naked or enveloped.
retinitis
An infection that causes retina to degenerate, leading often to
blindness, developed by most HIV patients showing reactivation of cytomegalovirus.
West Nile encephalitis virus
A virus that was first identified in New York City in 1999, has
spread southward and westward to include at least half of the States as of early 2002, and is expected to continue spreading because we have no means to contain it.
yellow fever virus
A well-known tropical virus for which travelers may need
vaccination.
lymphadenopathy
Swollen lymph nodes and spleen; characterizes toxoplasmosis.
malaria
A disease caused by four species of Plasmodium, with Plasmodium falciparum being responsible for about 80 percent of cases; death
usually results from anemia, kidney damage, heart attacks, or
cerebral hemorrhages.
merozoites
The transformed form of sporozoites that are infectious for red blood cells and escapes the immune system by constantly changing
the gene used to express their surface protein.
quinine
A chemical extracted from tree bark that has been used since the 1600s in the treatment of malaria, although resistance is becoming common.
toxoplasmosis
A disease that is caused by Toxoplasma gondii and damages its host through the growth of parasites called trophozoites in host tissues.
trypanosomiasis
A disease, also known as sleeping sickness, that is caused by two species of the genus Trypanasoma and often culminates in a coma that leads to death.
acquired immunodeficiency
syndrome (AIDS)
A collection of symptoms and conditions resulting from damage to the immune system causes Helper T cells (a particular kind of white blood cell) used by the
HIV virus to produce new virionsed by the human immunodeficiency virus, or HIV.
CD4 cells .
Helper T cells (a particular kind of white blood cell) used by the
HIV virus to produce new virions
protease inhibitor
An antiviral that prevents virus protease from breaking down large viral protein molecules into the smaller proteins needed for the assembly of virions.
combination therapy
A method, used by most HIV treatment regimens today, wherein two or more drugs are used simultaneously; extremely effective when at least one drug from each of the three classes is used, sometimes to the point where the virus can no longer be detected in the blood at all.
reverse transcriptase
An enzyme that converts its virion RNA into DNA once inside of a host cell and is critical to HIV's success.
gp160
A surface attachment protein that allows HIV to bind to T cell
receptors.
zidovudine (AZT)
The first and best known of about five available antivirals, a class of drug that acts against viral reverse transcription to inhibit replication.
human immunodeficiency
virus (HIV)
A retrovirus that systematically undermines the human immune
system, often leading to AIDS.
polyprotein
Several proteins combined.
ethanol
A two-carbon variety of alcohol.
fermentation
A beneficial process of microbial action on food; used in the production of wines, cheeses, breads, and so on.
pectinase
An enzyme with which flax is treated during linen production to release its cellulose fibers from a sugary, glue-like matrix of pectin for spinning.
protease
A family of enzymes that breaks down proteins and is commonly used for industrial purposes.
spoilage
A process of microbial action on food that renders the food useless as a nutritional source, or at least highly undesirable.
streptokinase
A bacterial enzyme that, when injected quickly into a heart attack patient, will break down blood clots and prevent further heart damage.
abyssal zone
Deep trenches in the ocean floor where microbes do in fact live, but in lower numbers than in other parts of the ocean, and in forms quite different from terrestrial organisms.
actinomycete
A group of gram-positive bacteria that grow in a branching filament structure, found in most soils, including deserts.
contaminated water
Contains infectious microbes or toxic substances.
ammonification
The second step in the nitrogen cycle, wherein proteins are degraded to amino acids and nucleic acids to nucleotides, and these subunits are further degraded to release nitrogen in the form of ammonia.
denitrification
The reduction of nitrite into gaseous nitrogen, often by Pseudomonas in the process of anaerobic respiration.
Azotobacter
A free-living, mutualistic bacterium that grows in the root nodules of leguminous plants and fixes nitrogen in areas such as grasslands.
eutrophy .
Changes in an area of water that render it hospitable to plant life and inhospitable to animal life, such as when microbes metabolize the available oxygen in a location
biochemical oxygen demand
(BOD)
A chemical process measuring the oxygen demanded by organisms from a body of water; conducted by measuring how much oxygen is utilized from a water sample over time.
genetic engineering
.
The linking together of various genes or gene fragments into a single DNA molecule
bioremediation
The use of living organisms as a remedy to an environmental
problem, such as adding phosphorous and nitrogen to water contaminated with crude oil to encourage the growth of naturally occurring bacteria that degrade crude oil.
greenhouse effect
A name for global warming, or climate change, referring to the way in which the earth's heat is held inside the atmosphere, much as heat is held within a greenhouse.
lichens
Mutualistic groups of algae and fungi, wherein fungi protect the
algae and help them
nutritionally, while the algae fix nitrogen from the air into forms used by fungi, and the algae also provide organic nutrients for the fungi.
nitrification
The synthesis of nitrate, accomplished in steps three and four of the nitrogen cycle by bacteria of the genus Nitrosomonas and the genus Nitrobacter respectively.
liquid phase
A step in the sewage treatment process.
nitrogen fixation
The reclamation of nitrogen gas from the atmosphere by bacteria
such as Azotobacter and Rhizobium.
littoral zone
This segment of the ocean is near the shoreline and contains most of the nutrients and microorganisms.
polluted water
Water containing obvious contaminates as indicated by its
appearance, smell, and so on.
methanogens
A group of strictly anaerobic Archaea that grow in swamps and manure and combine carbon dioxide with hydrogen to form methane and water.
potable water
Water that is fit to drink.
mycorrhizae
A fungal group that grows mutualistically with plant roots.
Rhizobium
Bacteria that use much energy to convert nitrogen gas into ammonia then into amino acids and nucleotides, resulting in very efficient nitrogen fixation that produces more than enough for the bacteria and the host plants.
sewage treatment
Degrades and removes particulate matter from water and kills harmful
microorganisms.
sludge
Solids left over after a water treatment.
water purification
Any process of cleaning water for use by humans, including those involving the removal of gravel, harmful chemicals, and microbes by the use of filtration and chemical processes.