Unit One Review
: organisms that are too small to be
seen with the unaided eye.
: microorganisms that are normally
found on or in the body and do not cause disease.
: rapidly growing cell
: microbe that causes disease.
: a study of bacteria.
: a study of fungi.
: the study of protozoa, parasites, and
: a study of immunity.
: the scientific study of viruses.
: the industrial application of
microorganisms, cells, or cell components to make a
: the study of the relationship
between microorganisms and their environment;
originated from Beijerinck and Windogradskyi.
: study of the mechanisms by which
microorganisms inherit traits.
: the study of the metabolism of
: the science of dealing with DNA and
protein synthesis of living organisms.
: the study of an organisms genes; used to
classify a microorganisms.
: bacteria degrade organic matter in
sewage. Bacteria also degrade or detoxify pollutants
such as oil and mercury.
: a new technique for
biotechnology. Bacteria and fungi can produce a variety
of proteins including vaccines and enzymes.
: the science of the classification of organisms.
: the idea that life could arise
spontaneously from nonliving matter.
: the theory that living cells arise only from pre
: adding microbes to your diet.
: acquired in hospitals; an infection that
develops during the course of a hospital stay and was not present at
the time the patient was admitted.
: vulnerable to disease caused by normal
: the enzymatic degeneration of carbohydrates in
which the final electron acceptor is an organic molecule (contains
carbon). For example, ATP is synthesized by phosporylation
(adding phosphate) and oxygen it is not required. Fermentation is
the process that yeasts use to convert sugars to alcohol in the
absence of air.
: the process of mild heating to kill particular spoilage
microorganisms or pathogens.
: without oxygen
Too small to be seen with the unaided eye.
Decompose organic wastes.
Are producers in the ecosystem by photosynthesis. These
include plants, algae, fungi, and cyanobacteria only.
Produce industrial chemicals such as ethanol (a solvent;
solvents dissolve substances) and acetone.
Produce fermented foods such as vinegar, cheese, bread,
beer, wine, and other useful products.
Produce products used in manufacturing (e.g. cellulose) and
disease treatment (e.g. insulin from
A few microorganisms are pathogenic (cause disease).
Knowledge of microorganisms allows humans to:
Prevent food spoilage
Understand aseptic technique to prevent contamination
and medicine, surgery, and in microbiology labs.
THE GERM THEORY OF DISEASE
Louis Pasteur, while he was studying
fermentation, found that microorganisms
are what cause disease.
the same pathogen must be present
in every case of the disease.
the pathogen must be isolated from
the diseased host and grown in pure culture.
the pathogen from the pure
culture must cause the disease when it is
inoculated into a healthy, susceptible laboratory
the pathogen must be isolated
from the inoculated animal and must be shown
to be the original organism.
Aristotle: Spontaneous generation:
darkness + dampness + grain = mice.
: established a system of scientific nomenclature. Each organism
has two names; genus and specific epithet (species).
invented the compound microscope
improved both the microscope and telescope.
: first observation of life microorganisms in teeth
scrapings, and rain water.
: first observation of cells. Devised cell theory: all living things are
composed of cells.
: demonstrated that maggots grew only in the meat in which the flasks
were not covered.
: cells arise from pre
existing cells; the beginning of the biogenesis
: showed that a silkworm disease was caused by a fungus.
advocated midwives to wash their hands when
going from one obstetric patient to another to prevent transmission
of for puerperal fever.
fermentation, pasteurization processes. Pasteur showed
that microbes are in the air, rain, spoiled foods, and cause disease
in animals. Discoveries included the relationship between microbes
and disease, immunity, and anti
microbial drugs (Germ Theory of
disease). His work led to the first vaccine (chicken cholera). He also
invented the rabies vaccine. His evidence was proof of biogenesis;
led to aseptic technique (by Lister) to prevent contamination in
laboratory and medical procedures.
Koch’s postulates, pure cultures; he proved that a bacterium
causes anthrax and provided the experimental steps (Koch’s
postulates) to prove that a specific microbe causes a specific
: studied sewage in cattle fields; used phenol for aseptic
surgery to disinfect and prevent surgical wound infections after
looking at Louis Pasteur’s work.
: invented the vaccine for small pox: he inoculated a person
with the non
deadly cow pox virus. The person became protected
from the deadly smallpox virus. He called this protection “immunity”.
He then made the first “vacca” (vaccination) for cows. His work
began when he saw milkmaids touching cows with lesions on their
udders; milkmaids were not contracting smallpox.
: developed first antibiotic drug: Salvarsan, to treat syphilis;
coined the term "chemotherapy".
: Discovered diptheria antitoxin.
discovered that mosquitoes transmitted malaria
discovered phagocytosis of white blood cells when he
observed a thorn in a starfish. He began the field of immunology and
studied the immune response.
: discovered the first antibiotic (penicillin). He discovered that
, when he found a green
mold growing on his Petri dish of bacteria.
Chain and Florey:
produced penicillin for large
scale manufacture during
: classification of Streptococcus.
: found a “transformation principle” in bacteria, known as DNA today.
virulent streptococci (can’t cause disease) were formed into virulent
Watson and Crick
: discovered the structure of the DNA molecule
discovered the role of messenger RNA in protein
Delbruck and Hershey:
replication mechanism and the
genetic structure of viruses.
discovered the disease
causing protein called a prion (smaller
than a virus).
SELECTED NOBEL PRIZES IN PHYSIOLOGY
Fleming, Chain, Florey
: keeps light from bending and allows lens
to be refracted.
: ability of two lenses to distinguish two
: focused in all lenses.
Depth of field
: how much of the background is in focus
at the same time that the foreground is in focus.
: a measure of the light
of a medium
: numerical aperture increases as
depth of field decreases.
: limits the useful magnification of the
Compare and contrast the seven major groups of microbes.
Explain the debate over spontaneous generation, name the
scientists involved in the debate, and describe their contributions,
stating whether they were for or against the theory of spontaneous
List ten microbiology pioneers that we studied, and describe their
contributions to microbiology.
Differentiate among the brightfield, darkfield, dissecting, phase
contrast, fluorescence, differential interference contrast, SEM, TEM,
and scanning probe types of microscopes, including their purpose,
function, or any advantages and disadvantages that we studied.
Differentiate between eukaryotic and prokaryotic cells.
Draw a picture of a typical prokaryotic cell and label it. Below your
drawing, pick any five structures you drew and discuss the structure
and function of each one.
MICROBES COMPARISON CHART
Peptidoglycan cell walls
Reproduced by binary fission
Uses organic and inorganic chemicals or photosynthesis for energy
Shapes are rod, coccus, spiral
Live in extreme environments
Include methanogens, extreme Halophiles (love salt), extreme thermophiles
(love heat and cold)
Cell walls have chitin
Heterotrophes: use only organic chemicals for energy
Molds and mushrooms are multicellular; consist of masses of mycelia,
which are composed of filaments hyphae.
Yeasts are unicellular
Absorb or ingests organic compounds
May be motile via pseudopods, cilia, or flagella
Cell wall contain cellulose
Uses photosynthesis for energy
Produces oxygen and organic food for other species
cellular intracellular parasites; lives at the expense of host
Contain either DNA or RNA surrounded by a protein coat
May have an envelope
Smallest of all microbes
Replicates in living host cell
Antibiotics do not work; requires antiviral agents
Helminthes: parasitic flat worms and tapeworms
Nematodes: parasitic roundworms
Endoparasites: animals that live inside other animals through fecal
Microscopic stages of life cycle
Parasite is in the bite of mosquito or bug; spreads infection in body
MICROBES COMPARISON CHART
Spontaneous Generation Theory
thought that the mice grew from the grain and
hay, and he coined the term “Spontaneous generation”
bees grew from honey and that flies grew from
maggots in meat were caused by flies laying eggs;
they only grew on the meat in which the jars were not
believed in spontaneous generation;
boiled nutrient broth to kill all microbes, put a non
cork in the flask, found that the broth grew microbes.
made a glass flask with an “S” shaped
bend in it so that bacteria could not enter into it but air
could get in. He placed chicken broth in the flask and
boiled it so that it was sterile and observed that there
was no bacterial growth in the broth.
COMPARISON OF MICROSCOPES
Dark objects are visible against a bright background.
Light reflected off the specimen does not enter the objective lens
Not for looking at live cells
Maximum resolution is 0.2µm and maximum magnification is
Stains are used on specimens
Light objects are visible against dark background
Used for live cells, cilia, flagella
Especially good for spirochetes
Uses special condenser with an opaque disc that eliminates all light
in the center
No staying required
Accentuates diffraction of the light that passes through a specimen
Good for live cells; good contrast
Most sensitive; cilia shows up
Uses two beams of light
Shows three dimensions
Has a prism to get different colors
Good for live cells (unstained)
COMPARISON OF MICROSCOPES
Uses ultraviolet light
Stained cells with fluorescent dye; energizes electrons and creates
No live cells
Quick diagnosis of TB and syphilis
Get flat images
Have vacuum pumps to allow electrons to float better
Stain with heavy metal salts
Shows sections of cell, revealing organelles
Requires an ultramicrotome
Surface view only
Needs a vacuum
No live cells
Physical probe scans the specimen
Raster scan: image is cut up into pixels and transmitted to computer
Not limited by diffraction
Slower in acquiring images
Maximum image size is smaller
One circular chromosome, not membrane
Paired chromosomes, membrane
Organelles present: Golgi complex, ER, mitochondria, chloroplasts
Peptidoglycan cell walls
Polysaccharide cell walls
Reproduce by binary fission
Reproduce by mitosis
No true nucleus; no nuclear membrane
True nucleus; nuclear membrane; also has nucleoli
Glycocalyx present as capsule or slime layer
Present in some cells that lack a cell wall
Plasma membrane has no carbohydrates and lack sterols
Plasma membrane has carbohydrates and sterols
Has a cytoskeleton
Ribosomes are small (70S)
Ribosomes are large (80S)
Prokaryotic Cell Drawing
Structure and Function of Prokaryotic
Consists of a phospholipid bilayer,
peripheral and integral proteins, and
Function: selectively permeable; allows for
passage of only certain molecules.
Gram negative organisms also have an
outer plasma membrane with LPS, which
is an antigen and contains a toxin.
Composed of peptidoglycan, which is a
series of two sugars, NAM and NAG,
connected with a peptide (or protein)
Function of cell wall: provides rigidity and
protection from osmotic lysis.
A sticky coating external to the cell wall,
made of polysaccharide, polypeptide, or
both. Made inside of the cell and secreted
to the cell surface.
May be either a capsule (organized) or a
slime layer (not organized).
Capsule function: to protect from
Slime layer function: allows for attachment
Made of a protein called flagellin.
Consists of a basal body, turning disc,
hook, and filament.
Function: ATP is used to turn the discs in
the basal body, which turns the whole
flagella to provide movement.
like structures around the cell, made
Function: Allows bacteria to attach to host.
Strains of bacteria that are without fimbrae
cannot attach and disease does not occur.
Special kind of fimbrae, but longer.
Function: allows two cells to attach for
conjugation and transfer of DNA from one
cell to another.