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.
_____________ are viruses that infect bacteria.
Bacteriophages are viruses that infect bacteria.
________ are small, circular DNA molecules
that carry genes from donor to recipient
in prokaryote ________.
Plasmids are small, circular DNA molecules
that carry genes from donor to recipient
in prokaryote conjugation.
examples of diseases caused by bacteria
tetanus, botulism, bubonic plague, lyme disease, c. diff, TB, gonorrhea, syphilis, cholera, strep, e. coli, sepsis
Are viruses living organisms?
Why or why not?
No -
they do not have a cell membrane,
and they do not independently reproduce or grow
Are viruses considered parasites?
Why or why not?
Yes -
bc they live in/on host,
cause harm to that host,
and can’t reproduce or grow independently of a host
Bacteria obtain energy & nutrients from
______ and ______ ______
(even __________ ones).
Bacteria obtain energy & nutrients from
organic and inorganic compounds
(even poisonous ones).
Metabolism of prokaryotes:
some ________ (tetanus)
some can switch ___/_______ (e. coli)
________ compounds
________ compounds (petroleum)
________ molecules (hydrogen, sulfur)
____________ (cyanobacteria, sulfur bacteria)
Metabolism of prokaryotes:
some anaerobic (tetanus)
some can switch an/aerobic (e. coli)
organic compounds
poisonous compounds (petroleum)
inorganic molecules (hydrogen, sulfur)
photosynthesis (cyanobacteria, sulfur bacteria)
____________ is the practice
of manipulating conditions
to stimulate breakdown of pollutants
by living organisms.
Bioremediation is the practice
of manipulating conditions
to stimulate breakdown of pollutants
by living organisms.
Bacteria reproduce asexually via
_______ _______ (_______ _______, rapidly).
Bacteria reproduce asexually via
binary fission (identical copies, rapidly).
Bacteria & Archaea differ in the biochemical structures of:
cell walls (____________ - bacteria only)
______ membranes
_________
____ polymerases
Bacteria & Archaea differ in the biochemical structures of:
cell walls (peptidoglycan - bacteria only)
plasma membranes
ribosomes
RNA polymerases
Bacteria reproduce sexually via __________:
the transfer of ________ ________ (donor to recipient)
across a ________ ________ or sex pilus.
Bacteria reproduce sexually via conjugation:
the transfer of genetic material (donor to recipient)
across a cytoplasmic bridge or sex pilus.
____________ is the process by which
facultative anaerobic bacteria survive
when there is no oxygen available.
Fermentation is the process by which
facultative anaerobic bacteria survive
when there is no oxygen available.
Gram-________ bacteria,
which are resilient to ________,
____ lipopolysaccharides.
Gram-negative bacteria,
which are resilient to antibiotics,
have lipopolysaccharides.
__________ were earth’s first organisms,
and the only life form for more than _______ years.
Prokaryotes were earth’s first organisms,
and the only life form for more than 1.5 million years.
_________ differ from other viruses in that
they use ___ as genetic material,
and ______ _________ transcribes its RNA into DNA
which is inserted into the ___ of the host cell.
Retroviruses differ from other viruses in that
they use RNA as genetic material,
and reverse transcriptase transcribes its RNA into DNA
which is inserted into the DNA of the host cell.
Which domains contain organisms that photosynthesize?
Bacteria & Eukarya
