Shared Flashcard Set

Details

Chapter 4
The Prokaryotes
55
Microbiology
Undergraduate 2
02/02/2011

Additional Microbiology Flashcards

 


 

Cards

Term
Differences in Prokaryotes and Eukaryotes
Definition
way DNA is packaged; composition of cell wall; no membrane bound organelles
Term
Flagella
Definition
counterclockwise motion propels bacteria forward; clockwise motion causes bacteria to stop and tumble
Term
Parts of a a Flagella
Definition
filament, hook, rod, rings
Term
monotrichous
Definition
single tail
Term
amphitrichous
Definition
tail on each end
Term
lophotrichous
Definition
multiple tails from one end
Term
pertrichous
Definition
multiple tails surrounding body
Term
axial filaments
Definition
component responsible for locomotion of the spirochetes; wrap around cell between cell wall and cell membrane; contract and relax
Term
pili
Definition
only found in gram (-) bacteria; long rigid projections; allow transfer of plasmid DNA between certain types of cells
Term
fimbrae
Definition
not present in all bacteria; short, bristle-like projections; mediate attachment to one another and/or surfaces
Term
glycocalyx
Definition
present in most but not all bacteria; protective outer covering; sometimes facilitates adhesion; in pathogenic bacteria, protect from the immune system; composed of polysaccharides and/or proteins
Term
slime layer of glycocalyx
Definition
thin, loose covering primarily protects from loss of water or nutrients
Term
capsule of glycocalyx
Definition
thick, dense covering that tightly binds to cells
Term
cell envelope
Definition
structural difference in gram (-) and gram (+) cells
Term
cell wall
Definition
comprised of polysaccahride peptidoglycan; prevents cell bursting in response to osmotic pressure; target of antibiotics; thick in gram (+)
Term
outer membrane
Definition
only present in gram (-) bacteria; between glycocalyx and cell wall; comprised of lipopolysaccharide outside and phospholipids inside
Term
phospholipids
Definition
anchor the outer membrane to the cell wall
Term
LPS
Definition
lipopolysaccharide; strong antigen; illicits a string immune response; protects cells from antibacterials and disenfectants; makes gram (-) cells more difficult to kill
Term
cell membrane
Definition
present in all bacteria; phospholipid bilayer with proteins dispersed (bacteria); bilayer of branched hydrocarbons (Archaea)
Term
functions of cell membrane
Definition
metabolism, transport, and secretion
Term
nucleoid
Definition
present in all bacteria; non-membrane bound; contains bacterial chromosome and associated proteins
Term
chromosomes
Definition
tightly coiled DNA; allows storage of DNA within cell; circular; consists of thousands of genes
Term
plasmid
Definition
not present in all bacteria; non-essential DNA; can fuse with chromosome; consist of a few genes; confers a growth advantage on cells; can be passed through pili and to daughter cells; important for genetic engineering
Term
ribosomes
Definition
present in all bacteria; made of RNA and protein; protein synthesis; characterized by size, which is measured in svedbergs (S)
Term
svedbergs (S)
Definition
measure size of ribosomes
Term
inclusion bodies
Definition
not present in all bacteria; stores of nutrients, gases, etc.; enclosed by a single-layer membrane
Term
granules
Definition
inclusion bodies that contain inorganic crystals and are not membrane bound
Term
cytoskeleton
Definition
present in a few types of bacteria; composed of the protein actin; arranged in helical ribbons around the cell just under the membrane; contributes to cell shape and structural stability
Term
cocci
Definition
sperically shaped bacteria
Term
bacilli
Definition
cylindrically shaped bacteria
Term
coccobacillus
Definition
bacilli; short and plump
Term
vibrio
Definition
bacilli; gently curved
Term
filamentous
Definition
bacilli; long and thread-like
Term
examples of spiral forms
Definition
spirillium; spirochetes
Term
pleomorphism
Definition
differences in the size and shape of bacteria of the same species; usually due to slight differences in cell wall structure
Term
endospores
Definition
dormant form of bacteria; allows cells to withstand extremes; can remain this way for thousands of years
Term
sporulation
Definition
the process of spore formation; initiated in response to depletion of nutrients from the environment; deposition of a thick protein coat around a chromosome and minimal amount of cytoplasm; protein coat made of peptidoglycan, calcium, and dipicolinic acid
Term
germination
Definition
the breaking of dormancy and return to the vegetative state; occurs in presence of water and at least one other agent; can become fully metabolically active within 2 hours
Term
bacterial classification
Definition
shape, arrangement, motility, growth characteristics, habitat, genetics
Term
rikettsias
Definition
very small, gram (-), obligate parasites, cause Rocky Mountain spotted fever and typhus
Term
obligate parasites
Definition
cannot survive, reproduce, or carry out metabolism outside the host cell
Term
chlamydias
Definition
obligate parasite, cause eye infection, STD, and pneumonia
Term
cyanobacteria
Definition
blue-green algae, gram (-), photosythetic and produce O2, float in water
Term
green and purple sulfur bacteria
Definition
photosynthetic but don't produce O2, common in sulphur springs, freshwater lakes, and swamps
Term
mycoplasmas
Definition
lack cell wall; cell membrane is more rigid due to the presence of sterols
Term
mycobacterium and nocardia
Definition
cell walls do not contain peptidoglycan
Term
archaea
Definition
prokaryotes in general structure; closely related to eukaryotes, rather than bacteria; unique RNA sequence; cell wall contains hydrocarbons rather than lipids
Term
thermophiles
Definition
archaea that live in extreme heat
Term
halophiles
Definition
archaea that live in extreme salt concentrations; contain a red pigment
Term
methanogens
Definition
archaea that convert CO2 and H2 to methane gas; important for greenhouse effect
Term
psychrophiles
Definition
archaea that live in extreme cold
Term
cellular arrangement of cocci
Definition
single; diplococci; tetrads; sarcinae; chains; irregular clusters
Term
cellular arrangement of bacilli
Definition
single; diplobacilli; streptobacilli; palisades
Term
cellular arrangement of spirilla
Definition
single; short chains
Term
cellular arrangement of spirochetes
Definition
single
Supporting users have an ad free experience!