Module 2 Flashcards
the presence of both an inner membrane and an outer membrane is characteristic of
a - gram + bacteria
b - gram - bacteria
c - both gram + & gram - bacteria
d - neither gram + nor - bacteria
b - gram - bacteria
*****for a bacterium with the ability to undergo sporulation, during which of the following “phase of bacterial growth” in liquid culture medium would this sporulation process start?
a - stationary phase
b - exponential phase
c - lag phase
d - transformation phase
e - conjugation phase
a - stationary phase
who developed the concept of sterility or the “germ theory of disease”
pasteur
what are specific adaptations that help a living organism colonies a specific environment
virulence factors
what are the major human pathogenic bacteria
- staph aureus
strep pyogenes
strep pneumonie
gram + rods & mycobacteria
E. coli & gram -
neisseria
haemophilus
bordetella
treptonema
perio & caries pathogens
what are the distinctions of bacteria from eukaryotic cells
- lack membrane organelles (MAIN THING)
- smaller
what is the most complicated thing in bacteria
cytoplasmic membrane
what is any isolated colony (every time) called
a strain
what is a culture of many bacteria called
species of bacteria
what is a pair of cocci
diplococci
what is a cluster of cocci
staphylococci
what is a chain of cocci
streptococci
what is a curved rod
vibrio
what is the primary characteristic for classification, and is observed at the same time as the shape & rearrangement by light microscopy
Gram-stain
what does Gram-staining have important implications for
structure of cell wall & other surface structures of bacteria
what does Gram-staining actually stain
the peptidoglycan layer of the cell wall
what are the steps of gram staining
- prepare a HEAT-fixed film of bacteria on a glass slide
- stain with CRYSTAL VIOLET for 1 min & rinse w/ water
- treat with Gram’s IODINE for 1 min & rinse w/ water
- briefly decolorize with ACTEONE or ETHANOL (a few seconds depending on thickness of film) and rinse w/ water
- Counterstain with basic FUCHSIN or SAFRANIN for 1 min & rinse w/ water
- BLOT DRY & view under OIL IMMERSION
what color is Gram +
puplre
what color is Gram -
red
what can a biochemical (metabolic) test kit tell you
what kind of sugars are made into acids
what are the 3 key characteristics often used in initial bacterial classification
- growth without oxygen?
- are spores formed?
- are they motile?
what is energy-generating metabolism which involves the Krebs cycle and oxidative phosphorylation by electron transport chains
respiration
what is conversion of the products of glycolysis to other forms without additional ATP gains
fermentation
what is an example of a spore-forming bacteria
Clostridium tetani (tetanus agent)
what kind of bacteria can form spores
only gram +
what can be used for +/- additional strain subtyping or confirmation
antigen testing & DNA techniques
what is the best way to compare bacteria
16S ribosomal RNA gene sequence alignment for similarity
what does a phylogenetic tree show
3 clusters corresponding to the 3 domains of life (bacteria, eucarya, archaea)
do entire genome sequences confirm 16S rRNA phylogeny
yes
what is the main bacteria for periodontal disease
Porphyromonas gingivalis
what is the most common strain of Escherichia coli?
K12
what is used to represent multiple species within that genus
ssp.
why is it possible to identify many important bacteria simply by shape and Gram stain type?
a - only a few are able to cause common human infections
b - there just aren’t that many types of bacteria around us
c- many bacteria share these simple characteristics
d - only a few bacteria have some of the shapes
a - only a few are able to cause common human infections
a bacterial virulence factor is __
a - all of these
b - flagella
c - reactive cell wall lipid
d - ability to grow in mucus
a - all of these
what is the difference between a bacterial species and a strain
a - a strain is any isolate
b - a species is a strain of bacteria
c - a train is a group of bacterial types
d - all of these
a - a strain is any isolate
what is the modern defining characteristic now used to define different types of bacteria?
a - 16S ribosomal sequence
b - motility and oxygen requirements
c - carbohydrate fermentation pattern
d - none of these
a - 16S ribosomal sequence
