Microbial Habitats Flashcards
The array of resources, physical
and biotic factors that are
present in an area, such as to
support the survival and
reproduction of a particular
species.
habitat
habitat is an array of resources, ___
and ___factors that are
present in an area, such as to
support the survival and
reproduction of a particular
species.
physical
biotic
A species habitat can be seen
as the physical manifestation of
its ecological ___.
niche
can be seen
as the physical manifestation of
its ecological niche
species habitat
s a distinct geographical region with specific climate, vegetation, and animal life.
biome
Bacteria and archaea reproduce ___only
asexually
Bacteria and archaea most commonly engage in a process known as
binary fission
where a single cell splits into two equally sized cells
binary fission
Other, less common of microbial reproduction processes can include
multiple fission
budding
sporulation
It has been determined that in a ____ (no food added, no wastes removed) bacteria will grow in a predictable pattern
close system or batch culture
four distinct phases of growth of growth curve
lag phase
exponential or log phase
stationary phase
death or decline phase
is an adaptation period, where the bacteria are adjusting to their new conditions.
lag phase
The length of the ___phase can vary considerably, based on how different the conditions are from the conditions that the bacteria came from, as well as the condition of the bacterial cells themselves.
lag
Actively growing cells transferred from one type of media into the same type of media, with the same environmental conditions, will have the shortest ___period
lag
Damaged cells will have a long ___period, since they must repair themselves before they can engage in reproduction.
lag
Typically cells in the lag period are synthesizing
RNA, enzymes, essential metabolites
typical cells are adjusting to environmental changes in their new environment (or media) such as
changes in temperature, pH, or oxygen availability
is marked by predictable doublings of the population, where 1 cell become 2 cells, becomes 4, becomes 8 etc.
exponential or log phase
Cells in the ____phase of growth are the healthiest and most uniform, which explains why most experiments utilize cells from this phase.
exponential or log phase
Due to the predictability of growth in this phase, this phase can be used to mathematically calculate the time it takes for the bacterial population to double in number, known as the
generation time
lternatively one can rely on the fixed relationship between the initial number of cells at the start of the exponential phase and the number of cells after some period of time, which can be expressed by:
N = No2^n
can be represented by t/n, with t being the specified period of time in minutes, hours, days, or months.
generation time
At some point the bacterial population runs out of an essential nutrient/chemical or its growth is inhibited by its own waste products (it is a closed container, remember?) or lack of physical space, causing the cells to enter into the
stationary phase
t this point the number of new cells being produced is equal to the number of cells dying off or growth has entirely ceased, resulting in a flattening out of growth on the growth curve.
stationary phase
their plasma membrane becomes less ___ and ___, with more hydrophobic molecules on the surface that promote cell adhesion and aggregation.
fluid
permeable
low-nutrient environments.
oligotrophic
During the stationary phase cells are also prone to producing or metabolites produced after active growth, such as antibiotics.
secondary metabolites
the number of viable cells decreases in a predictable (or exponential) fashion
death phase
It has been suggested that the cells thought to be dead might be revived under specific conditions, a condition described as
viable but not culturable
where a small population of the cells cannot be killed off
tailing effect
Where particular microorganisms
reside, characterized by a given
set of chemical, physical, and
biological conditions.
microbial habitats
microbial habitats composed of many micro
environments that differ in abiotic
conditions, such as
oxygen level
pH
temperature
mositure content
nutrient availability
light
Microorganisms occupy and adapt
to ___within habitats (gene
transfer used by microbes for
adaptation).
niches
Microorganisms occupy and adapt
to niches within habitats (___
___used by microbes for
adaptation).
gene transfer
allows bacteria to rapidly adapt to changing environments and spread traits like antibiotic resistance through mechanisms like transformation, transduction, and conjugation.
gene transfer
oxygen as an abiotic factor has range of states:
anoxoic
microoxic
oxic
is a place, typically aquatic but can also be underground, that lacks or has very low levels of dissolved oxygen
anoxic
is a small-scale environment characterized by low oxygen conditions, or reduced oxygen concentration, which supports a diverse range of microbial and other organisms adapted to these conditions.
microoxic habitats
is an environment, condition, or area where oxygen is present, as opposed to an anoxic habitat which lacks oxygen, or an anaerobic habitat which is completely free of oxygen
oxic
salinity as an abiotic factor has the range of states
hypersaline
marine
freshwater
refers to an area where the concentration of dissolved salts (salinity) is much higher than that of seawater
hypersaline environment
includes oceans, coral reefs, estuaries, mangroves, salt marshes, and the deep sea. These environments are home to a diverse range of marine life.
marine environment
he amount of dissolved salts in seawater, typically ranges from 33 to 37 parts per thousand (ppt
which environment
marine water
are bodies of water with low salt content, including lakes, ponds, rivers, streams, and wetlands, that support a vast array of plant and animal life, despite covering a small portion of Earth’s surface.
freshwater habitats
moisture level as abiotic factor range of states
arid
moist
wet
are characterized by low annual rainfall, high temperatures, and limited water availability, which leads to sparse vegetation and unique adaptations in the species that live there.
arid habitats
are areas characterized by ample moisture and often encompass wetlands, rivers, streams, lakes, and the transitional zones between them.
moist habitats
are areas saturated with water or covered by water, like marshes, swamps, bogs, fens, ponds, and salt marshes, supporting a wide range of unique flora and fauna adapted to these conditions
wet habitats
pH as an abiotic factor can have a range of states
acidic
neutral
alkaline
are environments with a pH lower than 7, and they can be both natural (like areas near volcanoes or geothermal vents) and man-made (like acid mine drainage or mine waste dumps).
acidic habitat
are environments with a pH level above 7, often found in soda lakes, arid/semi-arid regions, and saltwater environments, which can create challenges and opportunities for certain organisms.
alkaline habitats
temperature as an abiotic factor has a range of states
hot
warm
cold
light level as an abiotic factor has a range of states
aphotic
low level
bright
UV
are dark environments, whether aquatic or terrestrial, where there’s little to no sunlight, and organisms are reliant on other energy sources, like detritus or bioluminescence, rather than photosynthesis.
aphotic environments
plays a vital role in many habitats, influencing the behaviors, survival, and reproduction of various organisms, including nocturnal animals and plant
low level light habitats
range from aquatic ecosystems and polar regions to terrestrial habitats, with UV levels varying based on cloud cover, altitude, and surface reflectivity, impacting various organisms.
UV habitats
is a term for the position of a species
within an ecosystem, describing both the range of conditions
necessary for persistence of the species, and its ecological role
in the ecosystem
ecological niche
role of cyanobacteria as its niche
fixing nitrogen and producing oxygen during photosynthesis
two types of ecological niche
fundamental
realized
defined as the biotic and abiotic
conditions, such as shelter, food, and water, in which an
organism can live in the absence of pressures such as
predation, competition, disease, and other environmental
factors
fundamental niche
refers to the actual space occupied by a
species under real-world conditions, such as the presence of
competition, nutrient availability, and environmental stressors
realized niche
niche where all the things needed to survive is present
fundamental niche
Roughly 71% of the Earth’s surface is
occupied by water, >97% of which is
contained in the world’s oceans.
aquatic habitats
Roughly ___% of the Earth’s surface is
occupied by water, >97% of which is
contained in the world’s oceans.
71
Roughly 71% of the Earth’s surface is
occupied by water, ___% of which is
contained in the world’s oceans.
more than 97
Less than __of water is found in
streams, rivers, and lakes
1%
Major microbial players in aquatic
habitats include
phototrophs
heterotrophs
Earth’s water likely came from water-rich ___and ___that impacted the young, dry plane
asteroid
comet
which are
critical to primary production
autotrophs
which participate in the
cycling of carbon in aquatic habitats.
heterotrophs
temp range of -1.5 to 27oC at surface
salinity at 3.5%
what aquatic habitat
oceans
temp range of 0to 30oC
salinity at 0.001-0.05
what aquatic habitat
rivers
temp range of 4 to 50oC
salinity at 0.01
what aquatic habitat
freshwater lake
salinity average 12%
what aquatic habitat
great salt lake
inland water ecosystem
fresh water ecosystem
generally refers to rivers,
streams, lakes, ponds, and
ground- water
fresh water ecosystem
water that contains less
than 1000 mg/L of
dissolved solids by United
States Geological Survey
fresh water ecosystem
USGS
United States Geological Survey
A freshwater ecosystem is composed of water that contains less
than ___/L of
dissolved solids by United
States Geological Survey
1000mg
standing water
lentic ecosystem
lentic ecosystem includes
ponds
lakes
three subdivision of lentic ecosystem
littoral
limnetic
profundal
, shallow water region
with light penetration up to the
bottom in lentic ecosystem
littoral zone
open water zone up
to the depth of effective light
penetration
what subdivision of lentic ecosystem
limnetic zone
bottom and deep
water area beyond the depth of
effective light penetration
what lentic ecosystem
profundal zone
gradient in water ecosystem that exist
oxygen
upper waters can be ___ and warmer
oxic
upper waters can be oxic and warmer
epilimnion
, while the lower
levels are colder and sometimes anoxic (
hypolimnion
open water zone where light can penetrate
photic zone
deep water zone where the light cannot reach
aphotic zone
is an oceanographic phenomenon that involves wind-driven motion of dense, cooler, and usually nutrient-rich water from deep water towards the ocean surface.
upwelling
Seasonal changes in environmental (water) temperature bringing
___water to the lower reaches of the lake – affect microbial
populations in lakes.
oxygenated
The seasonal phenomenon where cooler, oxygen-rich water from the surface mixes with the deeper, colder layers of a lake, bringing oxygen to the lower reaches, is called
lake turnover
(an environment
with very low levels of
nutrients)
oligotrophic
(an
environment with very high
levels of nutrients)
eutrophic
negatively impacts microbial populations by lowering soil pH, leaching essential nutrients, and increasing aluminum toxicity
acid rain
running water ecosystem
lotic
lotic ecosystem includes
rivers and streams
two major zones of lotic ecosystem
rapid
pool
shallow water where velocity of current is great
enough to keep the bottom clear of silt and other loose
materials providing a firm substrate
rapid zone
deeper water where velocity of current is reduced
and silt and other loose materials settle to the bottom providing
a soft substrate
pool zone
affected by gravitational pull surface runoff
lotic ecosystems
micoorganisms in lotic ecosystems are those who can
survive the currents
tend to have many organic and
inorganic particles in suspension,
which limits the extent to which
light penetrates into the water
column.
lotic ecosystem
s a smaller body of flowing water that feeds into a river,
stream
is a larger, more continuous body of flowing water.
river
limit the level
of photosynthesis that occurs by
microorganisms within the streams.
turbidity
shading
springs of geothermally heated water, groundwater that comes in contact
with hot rocks, or in volcanically active regions, and magma.
hot springs
represent extreme environments in terms of temperature, and in some
cases, pH
hot springs
have low oxygen concentrations, suggesting the
presence of anaerobic or microaerophilic microorganisms. *
terrestrial hot springs
hot spring temperature limits ___
photosynthesis
yellowing in hot springs suggest
sulfur-rich materials
hyperthermophiles are often
chemoautotrophs
utilizing
carbon dioxide as their carbon
source, and acting as primary
producers within hot spring
habitats.
chemoautotrophs
characterize by general equality
in the composition and amount of
dissolved substances
marine ecosystem
characterize by general equality
in the composition and amount of
dissolved substances (average of
35 ppt) due to continuous
diffusion of sea water by means
of currents, tides, and storms
marine ecosystem
temperature ranges from 32ºC in
the tropics to -2.2ºC in the Arctic,
rarely fluctuates more than 5ºC
marine ecosystem
The Pelagic (open sea) environment is divided into the
neritic
oceanic
Extends from shore with water less than 200 meters.
neritic (nearshore)
neritic is divided into two zones
littoral (intertidal) zone
sub-littoral zone
Interval between high and low tides
littoral (intertidal zone
Below the littoral zone to a depth of 200 meters.
sub littoral zone
oceanic provinces
epipelagic
mesopelacig
bathypelagic
abyssopelagic
hadal
Water less than 200 meters
epipelagic
Water between 200 and 1000meters
mesopelagic
Water between 1000 and 4000meters
bathypelagic
Water deeper than 4000 meters
abyssopelagic
Depths below 6000 meters in deep sea trenches
hadal
sunlight penetrations has own divisions in oceanic provinces
photic zone
euphotic
dysphotic
aphotic
The upper part of the ocean where sunlight penetrates
photic zone
upper ½ of photic zone (usually to about 100 meters)
euphotic zone
lower ½ of photic zone
dysphotic zone
No light penetrates
aphotic zone
, also known as the benthic environment or benthic zone, is the ecological zone at the bottom of the ocean
benthic division
benthic division is subdivded into
continental shelf
continental slope
abyssal plain
the underwater edge of a continent that extends from the shoreline to the shelf break. It’s a relatively shallow area of ocean that’s part of the continent, not the ocean.
continental shelf
is a geological feature that connects the continental shelf to the deep ocean.
continental slope
re flat, vast areas of the ocean floor that extend from continental margins and reach depths of 3,000 to 6,000 meters
abyssal plains
zone that is affected by high tide or low tide (
intertidal zone
Tides, the periodic rise and fall of water levels, are primarily influenced by the
moon’s gravitational pull
illustrates the transfer of energy and nutrients through an ecosystem as one organism consumes another, starting with producers (like plants) and moving through various consumers and ending with decomposers.
food chain
s a collection of food chains that shows how energy and nutrients move through an ecosystem
food web
draw a food web
+!
draw a food chain
+1
larger and faster than most of their competition
top predators
ocean’s smaller organisms such as sardines that prey on herbivores, ultimately serve as nourishment for bigger, faster animals att top of food chain
carnivores
grazing animals devouring the see’s phytoplankton in staggering numbers
herbivores
every species in the sea’s food chain needs organic carbon to survive, and these tiny organisms produce it all
photo-autotrophs
samples species of photoautotrophs
phytoplankton
seaweed
seagrasses
sample species of herbivores in aquatic food chian
zoo plankton
sea urchin
parrot fish
sample species of carnivores in aquatic food chain
squid
sardines
snapper
sample species of top predators in aquatic food chain
sharks
tuna
seals
contain brackish water, a mixture of fresh and salt waters
estuaries
located where rivers flow into the oceans
estuaries
trap the nutrients brought in from the sea by the tides and
prevent the escape of nutrients carried by the rivers
estuaries
called as the “nurseries of the sea” because half of all marine
fishes develop in the protective environment of estuaries,
rich in larval shrimps, mollusks, and fishes
estuaries
important habitat for many vertebrates, located adjacent to estuarie
salt marshes
is created by weathering of rocks
soil
important habitats for
microorganisms, which play key
roles in providing nutrients to
plants.
soil habitats
affects the degree to
which nutrients and
microorganisms can move
around.
permeability
largest particulate of soil
sand
medium particulate of soil
silt
smallest particulate of soil
clay
combination of sand,
silt, and clay
loam
Refers to the horizontal layers in the soil.
soil profile
Each of the layer in soil profile is known
horizon
study and draw soil profile
+1
part of plants that
is decomposed
hummus
or organic layer because it
contains organic matter
o layer
most of the living organisms and
nutrients are found
a layer
layer in which leaching process
takes place
e layer
where does decomposer exists
A layer
area where rain leaches
E layer
also known as subsoil, contains
less organic materials and fewer
organisms. Minerals are often deposited
B layer
B layer is also known as
subsoil
- consist of weathered parent
material.
c layer
underground water is located at the
c layer
which refers to the bed rock
r layer
Also known as the microbe storehouse is the soil zone
surrounding the plant roots where the biological and
chemical features of the soil are influenced by the roots
rhizosphere
rhizosphere is located at the
a layer
where do anaerobic heterotrophic bacteria propagate in:
field
meadow forest
coniferous
wetland
wetland
where do aerobic heterotrophic bacteria propagate in:
field
meadow forest
coniferous
wetland
field or meadow forest
where do nitrifying bacteria propagate in:
field
meadow forest
coniferous
wetland
field
where do denitrifying bacteria propagate in:
field
meadow forest
coniferous
wetland
field
where do nitrogen fixing bacteria (aerobes) propagate in:
field
meadow forest
coniferous
wetland
field
where do nitrogen fixingbacteria (anaerobes) propagate in:
field
meadow forest
coniferous
wetland
meadow forest
where do anaerobic butryric acid bacteria propagate in:
field
meadow forest
coniferous
wetland
wetland
draw the soil food web
+1
Is an orange-yellow to black coating found on exposed rock surfaces in arid
environments
desert or rock varnish
Pore spaces within rocks are a widespread habitat for microorganisms
desert or rock varnish
desert or rock varnish are Pore spaces within rocks are a widespread habitat for microorganisms called
endolithic microorganisms
Protect microbe from radiation from the sun, especially ultraviolet
radiation, desiccation, and large variations in temperature in desert
rock varnish
influence the
nature of the microbial communities that live within the rock.
Mineral composition of rock, nature of the pore spaces
nutrient sources
climate
the frequency of precipitation
extend a few meters to
thousands of meters below the
Earth surface and offer a variety of
microbial habitats.
caves
in which caves
form is often limestone or volcanic
parent rock
Parent rent rock in which caves
form is often
limestone or volcanic
Cave habitats beyond ___ zones are characterized by very
high relative humidity that approaches 100%, total darkness, low nutrient
levels, and stable temperatures.
entrance
twilight
t is the area nearest the cave opening, receiving sunlight and experiencing variable temperatures and humidity
entrance zone
, there’s less light, so plants don’t really grow there. The temperature remains a bit more constant but may still fluctuate in conjunction
twilight zone
Exceptional habitats within caves may occur where reduced gases vent
into the cave or bat colonies deposit large amounts of ___.
guano
“Largest habitat for microorganisms on earth,” which may harbor up to 40%
of Earth’s archaeal and bacterial biomass.
groundwater
- lack of readily available, fresh carbon and sunlight.
groundwater
One of the key features of groundwater habitats is their ___
interconnectivity, which allows for the transfer of nutrients and organisms
over large areas
hydrologic
sediments at the ocean’s bottom have revealed cells up to 800 m down in
the bottom sediments
deep subsurface
included organisms such as methanogens, acetogens, various
heterotrophs, and sulfate and iron reducers and revealed indications of the
energy sources available with hydrogen generated by rock–water
interactions playing a key role.
deep subsurface
Dust storms loft desert soil particles, often with attached microorganisms,
high into the air.
atmospheric habitats
Microorganisms survive over long distances and times, to land on distant
terrains.
atmospheric habitats
group or taxa of microorganisms that differ from other groups
or taxa on a particular environmental parameter
population
tends to; explain the distribution patterns
of organisms by studying their
physiology, their interactions with other
organisms, the physiochemical
properties of their environment, and
genetic changes at the individual and
population levels in response to
environmental factors
microbial population ecology
creation of new species
of organism
speiation
The acquisition of new genes through ___transfer may allow bacteria and archaea to
exploit new niches
horizontal gene transfer
horizontal gene transfer can be through
transduction
conjugation
transformation
results in rapid viral reproduction, causing the host cell to burst and release many new viruses
lytic cycle
involves the virus’s genetic material integrating into the host’s DNA, leading to replication without immediately killing the host
lysogenic cycle
s a form of horizontal gene transfer where bacteria acquire genetic material from other bacteria through bacteriophages (
transduction
major mechanism for this transfer in bacteria, where genetic material (often plasmids) is passed between bacteria through direct cell-to-cell contact
conjugation
is a process of horizontal gene transfer in which bacterium picks up genetic material (naked DNA) from the neighboring environment, or genetic material is transferred from one bacterium to another through surrounding media.
transformation
