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26 Cards in this Set
- Front
- Back
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Microorganisms are diverse in (4)
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Appearance
Metabolism Physiology Genetics |
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What are the main fxns of microbes?
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nitrogen fixation (capture inorganic N)
replenish oxygen biodegradation (recycle, C, N, O) |
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Both Bacteria & archaea domains are _______________, thus DNA is stored in nucleoid & they lack organelles
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prokaryotes
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Domain Eucarya are ___________, have a true nucleus & cellular organelles
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eukaryotes
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__________ are obligate intracellular parasites
What does this mean? |
Viruses
only multiply w/i host, need replication machinery & nutrients of host to survive |
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__________ are protein coat + nuclei acid
_________ are protein only |
viruses
prions (protein only) |
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Prokaryote shapes
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rods (rod shaped, also called bacillus, bacillus also name)
cocci (round) spirillum (spiral) |
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_________________ chromosomes are circular, single or double stranded, super-coiled, & located w/i nucleoid
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Bacterial chromosome
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Bacteria also contains DNA w/i _____________
How does this DNA differ from chromosomal DNA? |
plasmids
small circular double-stranded toxin producing (antibiotic resistant) transferred & replicated independently |
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Bacterial ribosomes is _____ composed of what 2 subunits?
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70S
(50S & 30S subunit) (eukaryotes have 80S ribosomes) |
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Where is the electron transport chain & energy production occurring in bacteria?
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cytoplasmic membrane
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The cell wall contains ________________
What 2 major subunits is this component made up of? |
peptidoglycan
NAM & NAG (covalently linked by glycan) |
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what part of the bacterial is recognized by the immune system?
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cell wall
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Describe Gram stain procedure (4 steps)
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1. Crystal violet- stains cells purple (both +/-)
2. Iodine- locks in purple stain (both +/-) 3. Alcohol- decolorizes gram (-) only 4. Safranin- counterstrains gram (-) red, gram (+) remain purple |
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What is the determining step of gram staining?
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step 3--> Alcohol decolorizer
if bacteria decolorizes= gram (-) if it remains purple = gram (+) |
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Difference in structure btwn gram (+) & gram (-)
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cell wall*
-gram (+) contains more peptidoglycan & teichoic acid (neg charge) -gram (-) peptidoglycan layer is w/i periplasmic space, (btwn outer membrane & cytoplasmic membrane), outer membrane w/ LPS |
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The gram (-) outer membrane contains LPS, what is this composed of?
what does this provide? |
Lipid A & O-specific polysacharide side chain
provides resistance to antimicrobial medications, inherent toxic activity, endotoxin |
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What does the body recognize, that alerts is of the presence of invading bacteria, leading to stimulation of immune response?
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Lipid A on the LPS molecule
(lipid A also anchors LPS in lipid bilayer) |
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LPS also can cause fever & shock, what does LPS release?
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DIC (disseminated intravascular coagulation)
(leads to inappropriate activation of coagulation cascade & fibrinolysis) |
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How does mycoBACTERIUM sp. differ from other gram (+) bacteria?
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contains mycolic acids (waxy lipids) w/i peptidoglycan cell wall-->
prevents gram-stain from working* use acid-fast stain instead |
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How does mycoPLASMA sp. differ from other bacteria?
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has no (peptidoglycan) cell wall*-->
can't be recognized as easily (many meds that target cell wall dont work) has steriod incorporated into membrane |
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What is glycocalyx?
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slime/capsule/gel layer
-fxn for protection/attachment *biofilms |
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Fxn of Flagella
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motility
chemotaxis (towards food, away from toxins) |
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Pili enable attachment of cells to specific __________ on fimbraie
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adhesins
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4 most common endospore producers
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Clostridium botulinum (botulism)
Clostridium perfringens (gangrene) Clostridium tetani (tetanus) Bacillus anthracis (anthrax) |
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Endospores can survive dangerous environments & germinate into active vegetative cells. (resistance)
What is the process of spore formation? |
sporulation
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