CH 20 Flashcards
_______ are aggregates of bacteria
that secrete _____________
and _______ _______
(against antibiotics, disinfectants, etc).
ex: _______ _______
Biofilms are aggregates of bacteria
that secrete polysaccharide
and provide defense
(against antibiotics, disinfectants, etc).
ex: dental plaque
Lis the 3 bacterial shapes:
spherical (cocci),
rod-like (bacilli),
corkscrew (spirilla)
Which prokaryote has peptidoglycan in cell walls?
bacteria
___ ________ account for the creation
of new types of bacteria.
DNA Mutations account for the creation
of new types of bacteria.
_______-_______ _______
capture _______ ___ (N2) from soil
and convert it to _________ (NH4+),
making it accessible to plants.
Nitrogen-fixing bacteria
capture nitrogen gas (N2) from soil
and convert it to ammonium (NH4+),
making it accessible to plants.
Viruses replicate by:
______ a host cell,
where ___/___ causes the cell
to reproduce ______ __________,
which ______ ______ into viruses,
which then _____ ____ host cell.
Viruses replicate by:
entering a host cell,
where DNA/RNA causes the cell
to reproduce viral components,
which assemble rapidly into viruses,
which then burst from host cell.
A bacterium can survive long periods of ________
by producing an ________ (consisting of
________ material, ________, & a protective coating),
which doesn’t ________, just remains stable;
when ________ ________ arise
(i.e. contact with water), it resumes life.
A bacterium can survive long periods of dessication
by producing an endospore (consisting of
genetic material, enzymes, & a protective coating),
which doesn’t metabolize, just remains stable;
when favorable conditions arise
(i.e. contact with water), it resumes life.
What are 3 roles of bacteria in ecosystems?
nitrogen fixation
recycling organics
bioremediation
How many known clades are in the Bacteria domain?
30, including:
cyanobacteria, firmicutes, proteobacteria
How does the flagellum of a prokaryote move?
wheel-and-axle rotation
What are 5 types of extreme environments
that can bacteria can live in?
temps - boiling / freezing, e.g. antarctica / hot springs
time - stable, >250million years
pressure - e.g. bottom of sea floor
chemical - e.g. high salt desiccation - e.g. anthrax spores as bioterror agent
acidic or alkaline - vinegar/ammonia
Viruses are ________ and
attack only ________ host cell(s).
Viruses are specialized and
attack only specific host cell(s).
Ways bacteria provide benefits to humans:
make _______,
_____ _______ from dead organisms for reuse,
______________ (e.g., oil spill clean up),
_______ _______ in gut & vagina,
_________ of _____ (cheese, yogurt);
in animals, they break down _______.
Ways bacteria provide benefits to humans:
make vitamins,
free nutrients from dead organisms for reuse,
bioremediation (e.g., oil spill clean up),
maintain balance in gut & vagina,
production of foods (cheese, yogurt);
in animals, they break down cellulose.
Viruses are composed of:
___/___ - hijacks host cell for _________
______ ___ - enables entry into ___ ___
Viruses are composed of:
DNA/RNA - hijacks host cell for reproduction
Protein coat - enables entry into host cell
Bacteria & Archaea are both
________, ________, and ____ (micrometers).
Bacteria & Archaea are both
prokaryotic, unicellular, and small (micrometers).
____________ are blue-green ‘algae’
that ____________ via ________ in membranes.
Cyanobacteria are blue-green ‘algae’
that photosynthesize via chlorophyl in membranes.
____-________ bacteria lack lipopolysaccharides.
Gram-positive bacteria lack lipopolysaccharides.
_______ are infectious particles composed of only short ___ (no protective coating) that attack ______.
Viroids are infectious particles composed of only short RNA (no protective coating) that attack plants.
Bacteria exchange genetic information via the __________ ______ (or, sex _____).
Bacteria exchange genetic information via the cytoplasmic bridge (or, sex pilus).
Prokaryotes are classified using:
________ sequences, ______, means of ________,
________, _______ requirements, _______ appearance,
and _____-________ characteristics.
Prokaryotes are classified using:
nucleotide sequences, shape, means of locomotion,
pigments, nutrient requirements, colony appearance,
and gram-staining characteristics.
types of genetic material in viruses
DNA or RNA, single or double stranded (nucleic acids)
______ are misfolded proteins (PrP)
in the membranes of ______;
when ingested,
they cause ______ PrP to become misfolded,
leading to ____ damage & death.
examples: ____ - via cannibalism, Creutzfeldt-______ Disease, ______ (in sheep), ____ ____ disease
Prions are misfolded proteins (PrP)
in the membranes of neurons;
when ingested,
they cause benign PrP to become misfolded,
leading to CNS damage & death.
examples: Kuru - via cannibalism, Creutzfeldt-Jacob Disease, Scrapie (in sheep), mad cow disease
What does sulfur bacteria use instead of water for photosynthesis?
hydrogen sulfide (H2S)
There are ___ known clades in Archaea, including c____________ & e____________.
There are 5 known clades in Archaea, including crenarchaeota & euryarchaeota.
