Prokaryote Flashcards
In the word “Prokaryote” mean?
Pro = before, karyon = nucleus
In Prokaryotes they have; no _______, no _________, no __________
nucleus; organelles; cytoskeleton
What are the three domains of life?
1) Bacteria and 2) Archaea (both prokaryotes), and 3) Eukarya
In Bacteria, _______ collection of many species
Diverse
In Bacteria, So widespread we have only ___________ about their ecology
generalizations
In Bacteria, Key to success is _____________
metabolic diversity
More _________- in your gut than all people who ever lived
bacteria
What are the important biosphere functions in bacteria?
Cycle nutrients (decomposers)
Some trap energy from sun or chemicals
Some help animals digest food
What are the four common bacteria shapes?
coccus, cocci
bacillus, bacilli
vibrio, vibrios
spirillum, spirilla [rigid]; spirochaetes [flexible]
What type of shape is coccus, cocci?
Spheres
What type of shape is bacillus, bacilli?
Rods
What type of shape is vibrio, vibrios?
Comma-shaped
What type of shape isspirillum, spirilla [rigid]; spirochaetes [flexible]?
Spirals
What is the anatomy of a bacteria?
No nucleus; a supercoiled chromosome
Plasma membrane; most have a wall, too Cytoplasm contains ribosomes
Most bacteria have a cell wall of ____________(amino sugar polymer)
peptidoglycan
Some bacteria also have __________- capsule
polysaccharide
Gram staining separates most into two groups and they are?
Gram-positive and gram-negative
What is a gram-positive tell?
stain blue to purple; thick exterior peptidoglycan layer
What is a gram-negative tell?
stain pink to red; thin peptidoglycan within lipopolysaccharide envelope
Some bacteria have rotating _________ made of protein _________
flagella; flagellin
Some bacterial cells have ________ (shorter, hairlike) for __________ to other cells or surfaces
fimbriae; adhering
In bacterial reproduction, ______ replicates first
DNA
In bacterial reproduction, Cells divide by _______ (asexual)
fission
Bacteria may exchange DNA fragments which is called?
conjugation
pick up DNA from environment which is what?
transformation
__________ rate means prokaryotes can evolve quickly
Rapid reproductive
What are the different types of bacterial metabolism?
Obligate anaerobes Facultative anaerobes
Obligate aerobes
What is Obligate anaerobes?
cannot live if O2 present
What is Facultative anaerobes?
shift between anaerobic & aerobic modes
What is Obligate aerobes?
cannot survive without O2
What are the different ways bacterial can get its nutrition?
Photoautotrophs
Photoheterotrophs
Chemoautotrophs
Chemoheterotrophs
What are Photoautotrophs and examples?
photosynthesizers (algae)
What are Photoheterotrophs?
use sunlight as energy, but use organic compounds as a source of carbon (purple nonsulfur bacteria)
What are Chemoautotrophs?
energy from oxidizing inorganic substances (deep sea thermal vent bacteria)
What are Chemoheterotrophs?
obtain energy and carbon from organic compounds (animals; most known bacteria and Archaea))
Some bacteria metabolize ________________
sulfur or nitrogen
In some bacteria, they use nitrogen or sulfur compounds (not oxygen) as __________
electron acceptors
What is the important role in Diazotrophs?
key role in nitrogen cycle: “fix” nitrogen gas (N2) into form usable by plants/animals
Plants/animals depend on bacteria for________
nitrogen
___________ of dead organisms and return of nutrients to soil
Decomposition
_______________________: descendants of once free-living bacteria
Mitochondria & chloroplasts
Cows & other ruminants (grazers): depend on ____________ to digest cellulose
prokaryotes
Bacteria produce vitamins B12 and K in _______ intestines
human
What are the rules for showing a particular microorganism causes a particular disease?
The microorganism must always be found in individuals with the disease
The microorganism can be taken from the host and grown in pure culture
A sample of the culture produces the disease when injected into a new, healthy host
The newly infected host yields a new, pure culture of microorganisms identical to those obtained in the second step
Pathogen definition: it must?
Arrive at the body surface
Enter the body
Evade detection/defenses
Multiply inside host
Infect new hosts
What determines seriousness of infection?
Invasiveness of pathogen
Toxigenicity of pathogen
What are Endotoxins and examples?
lipopolysaccharides from outer membrane of Gram negative bacteria; cause fever, vomiting, diarrhea; Salmonella, Escherichia coli
What are Exotoxins and examples?
produced & released by living, multiplying bacteria; tetanus
Enotoxins can be______ toxic or _________; no fever
highly; fatal
What are the different ways of Classifying prokaryotes in the past?
color, shape, staining, antiobiotic resistance used to classify
What are the different ways of Classifying prokaryotes today?
nucleic acid sequences (especially ribosomal or rRNA) giving clues
What are the Bacterial lineages?
Proteobacteria
Cyanobacteria
Spirochetes
Proteobacteria are the _______ group
largest
Proteobacteria is the origin of_________ in Eukarya
mitochondria
Example of Proteobacteria
E. coil
Cyanobacteria is important _________
photoautotrophs
Cyanobacteria is the origin of ____________ in Eukarya
chloroplasts
Examples of Cyanobacteria
Anabaena; Oscillatoria: colonial, filamentous
Spirochetes resemble ________
corkscrews
Examples of Spirochetes
Some human parasites (syphilis: Treponema); others free-living
Chlamydias are ________ parasites
Intracellular
Examples of Chlamydias
Eye infections, STD, & some forms of pneumonia
Firmicutes: most are gram-________
positive
In Firmicutes, some _______ milk to yogurt or cheese.
Some produce __________: heat-resistant resting structures
ferment; endospores
Examples of Firmicutes
Bacillus and Clostridium
Actinobacteria: elaborately branched __________
filaments
Examples of Actinobacteria
Most antibiotics (including streptomycin) from actinobacteria
In some bacteria have Endospores that have a __________ coat and a amazingly long __________
Tough protein; dormant span
Examples of bacteria that have Endospores
Bacillus anthracis, Clostridium botulinum, Clostridium tetani
Less diverse than Bacteria are the?
Archaea
Many archaea live in _________ environments?
harsh
Archaea have No ________ in cell wall and they have
a unique membrane _______
peptidoglycan; lipids
Some Archaea are ____________________
Thermophiles & acidophiles
