Microbial Ecology Flashcards
Population
same species, same place
Community
multiple species living together
what is the growth rate?
variable growth rate
storage polymers
polysaccharides (etc)
what is the nutrient cycling?
redox reactions & metabolism
Redox reaction is the transfer of _______
electrons
habitat (location, nutrients available, what it interacts with)
Niche
Temperature can define what ______ are found in that niche
microbes
Resources & _______ that govern microbial growth in nature
conditions
Redox reactions play a key role in ________ rxn
metabolic
natures way of reusing carbon atoms is the ___________
carbon cycle
microbes play a critical role in the cycling & it is necessary for ________ survival
humans
aggregation of microbes together on a surface & enclosed in an adhesive matrix
biofilm
microbes like to be attached to _____
surfaces
matrix is composed of
polysaccharide, nucleic acid, protein
matrix is protected from
____________ & biocides
Grazing (protozoans, immune system)
other stresses (Extreme temp changes)
antimicrobials
quorum sensing is the ______ between the biofilm
communication
diversity is always a component of a __________
biofilm
where do you find the biofilms?
environment (mats around the house), industrial (Water chemical bioremediation), health (dental plaque infection)
microbial mats have very _____ biofilms
thick
biofilms: ___________ of microorganisms working together
community
Gradients:
nutrients environmental factors
Each layer has a different set of ________ working together & making sure the next layer has what is needs for survival
microbes
as you go deeper in the biofilm oxygen levels _______ & pH levels decrease (becomes more acidic)
decrease
______ makes up the biofilm & the microorganisms are working together to make sure they have what they need for survival
Community
O Horizon: __________ plants
undecomposed
A horizon: lots of organic matter, lots of ________
microbes
B horizon: little organic matter, less __________ activity
microbial
Rhizosphere: soil surrounding plant ____
root
Rhizosphere has a _____ microbial abundance
high
numerous microenvironments in a single particle of _____
dirt
what makes up the majority of the groups in soil?
proteobacteria, bacteriodetes, acidobacteria
farming reduces _____ of the soil
richness
pollution influences microbes that can live in that ________
niche
microbes live at least ____ km deep
3
microbes can live in
biofilms
terrestrial
aquatic ( freshwater & marine )
true
freshwater: More shallow waters
lakes & streams
freshwater: seasonal changes
- temperature
- inputs of ____________ & _______________ nutrients (ground runoff, waste water)
endogenous & exogenous
freshwater: affect oxygen & carbon cycles
- changes in microbial content
- algal, ___________ blooms
cyanobacterial
freshwater: input (exogenous nutrients), O2 levels decrease, bacteria increases, algae & cyanobacteria increase, & O2 levels come back to normal, algae & cyanobacteria decrease
freshwater
algae & cyanobacteria can build up water waste and change amount of oxygen & the amount of microbes that live in the environment
overgrowth
Microbes present in freshwater
proteobacteria, actinobacteria, Bacteroidetes, cyanobacteria
microbes present in terrestrial environment
proteobacteria, bacteriodetes, actinobacteria
marine environment: much deeper
oceans
marine environments have lower _______, fewer microbes, small cells, & temperatures more constant than freshwater
nutrient
oxygen minimum zone: biological activity can use up all of the _________ in a niche
oxygen
oxygen minimum zone: oxygen demands __________ oxygen availability
exceeds
you lose more ______ in oxygen minimum zones than archaea
bacteria
both archaea & bacteria _______ in oxygen minimum zones
decrease
open oceans: phototrophs
Prochlorococcus
Prochlorococcus:
- half of photosynthetic biomass & primary production in _____ & subtropical oceans
tropical
open ocean: chemoorganotrophs
Pelagibacter
Pelagibacter: Grows ____ nutrient levels, small size, small compact genome
low
open ocean you find 10x more _____ than bacterial cells
viruses
hydrothermal vents have their own ______ environment
microbial
deep sea:
chemotrophs, piezophiles, psychrophiles, hydrothermal vents
hydrothermal vents: thermophiles, hyperthermophiles, chemolithotrophs, bacteria & _________
archaea
symbioses: prolonged microbial interaction with another _____
organism
parasitic: microorganism benefits, ____ harmed
host (infection in a human)
commensal: one benefits, the other ________
unharmed
mutualistic: both organisms are _______
benefiting
symbioses between microbes:
lichens
Lichens: mutualism
_______ & phototroph
fungus
phototroph provides _____ matter
organic
fungus provides _______ to grow in, inorganic nutrients, protection from drying
firm anchor
symbioses with plants:
rhizobia
Rhizobia attaches to _____ & helps fix nitrogen giving the plant much better growth
root
Rhizobia:
legume _____
root nodules: fix nitrogen
mutualist
commensal blocks border from a ________ pathogen
professional
when fungus is attached to the root it helps the plant ______ (rhizobia)
grow
symbioses with invertebrates
wolbachia & attine
wolbachia: ______ parasite of insects
skews the sex-ratio
control the mosquito populations
heritable
wolbachia: control mosquito population by decreasing _______ transmission
disease
ants feed the fungus, & then the fungus eats the ant
attine (mutualistic)
escovopsis: destroys ______
garden
yeast inhibits _________
pseudonocardia
actinobacterium (pseudonocardia) inhibits ______
escovopsis
symbioses with mammals:
ruminants
rumen: digestion of plant __________
polysaccharides (cellulose)
cellulolytic microbes release _________
glucose (Mutualistic)
fermenters: break down _______ fatty acids
volatile (animal energy source)
cow doesn’t survive without
anaerobic bacteria, archaea, eukaryotes (firmicutes, Bacteroidetes, archaeal methanogens)