Chapter 21 Flashcards
_______ is the scientific study of how organisms interact with their environment
Ecology
Environmental characteristics are classified into two major components.
Abiotic and biotic Characteristics
___________: Physical and nonliving chemical characteristics, such as temperature, soil moisture, or CO2 availability
Abiotic characteristic
__________: Relation of living organisms with the environment, ex: population density or bacterial load
Biotic characteristic
Four levels of ecology
1) organismal ecology
2) population ecology
3) community ecology
4) ecosystem ecology
Organismal Ecology
- This is the simplest level of ecology
- It exposes how well individuals organisms cope with the challenges of their abiotic charateristic
Population Ecology
- At this level, ecologists study populations: groups of individuals of the same species living in the same area
- This focuses primarily on population-level factors such as population density and growth
Community Ecology
- This is the study of species assemblages and their environmental interaction
- At this level, ecologists study the structure and organization of how all the species in an area interact together
Ecosystem Ecology
- This is the most dynamic and complex type of ecology
- focus on energy flow and the cycling of chemical among
__________ are what largely determine which type of organism can live where.
Abiotic
Specific organisms are specialized to live in _________.
specific environments
In the desert, organims deal with ______________.
heat and water loss.
In temperate climates, organisms deal with ____________.
seasonal changes
Energy in all ecosystems in ultimately traced back to __________, which plants transfer into chemical energy.
Solar energy
The more plants, the greater potential for diversity of ______.
life
Availability of sunlight affects
aquatic and terrestrial environments
A challenge in the water is____________.
light fading with depth
On land shading by other organisms is a _______.
problem
Plants and animals have different strategies to cope with ____________ sunlight
little or intense
Environmental temperature has a critical effect on an organisms _______.
metabolism
Few organisms can maintain a sufficiently active metabolism at temperatures close to ____.
0 c
Temperatures above________________ of most organisms.
45’c destroy the enzymes
Some bacteria and archaea are unique because they can live in extreme temperatures _________ _________ __________ __________.
have enzymes that function optimally at extremely high tempertures
Marine organisms have to balance their cells against the ___________ found in sea-water
high salt concentration
Freshwater organisms must regulate water intake because they live in a ___________________.
Hypotonic environment
Terrestrial organisms must conserve ______ and avoid _______.
water
water loss
because water exists as three forms on earth, organisms need to be able to utilize these forms depending on their ___________.
environment
Aquatic but not terrestrial ecosystems are more limited by (3)
- The levels of dissolved oxygen and salinity
- currents
- tides
______, ______, and ______ can also effect an organisms’ use of their environment of growth patterns
Wind patterns
storms
and fire
Many plants depend on wind to _____________.
disperse pollen and seeds
other organisms require wind to blow in _________.
nutrients
The distribution and abundance of plants is often determined by the (2)
- Availability of nitrogen and phosphorus
- the structure, pH, and nutrient content of the soil
In many aquatic ecosystems the growth of algae and photosynthetic bacteria is often limited by levels of (2)
- Nitrogen
- Phosphorus
Catastrophic disturbances can have huge impact on biological communites (2)
-Some of these disturbances are irregular and random
(earthquakes, volcanism, fire)
-Other disturbances have a certain degree of periodicity
(hurricanes, tornadoes, floods)
On occasion, these can actually drive variation, because this selects for organisms favored under ______.
stress
After disturbance, ______________ (re-growth of habitat) take place
ecological successions
Because organisms continually interact with their environment, ____________ will select for certain phenotypes and against others
Natural selection
The three areas of adaptation in which natural selection acts on a phenotype are _________________. (3)
Physiology, anatomy, and behavior
___________ is a physiological adjustment to an environmental change
Acclimation
Among vertebrates, birds and mammals can tolerate the greatest temperature extremes because they are _________.
Endotherms
While the metabolism of ectotherms, like reptiles (cold blooded animals) fluctuates with their environment, and __________ can tolerate only limited climates.
Ectotherms
There are many anatomical features that allow organisms to cope with environmental challenges (1)
- There include changes in body shape or having specific anatomical features
Reversible change, _________________ is an example of acclimation.
Such as a heavier fur coat in response to cold
Most behavioral adaptations are limited to animals since plants lack the ability to _____________.
move around
Behavioral Responses include (3)
- Specialized mating
- Ectotherms may shuttle between sun and shade
- Migratory birds travel great distances in response to changing season
A Biome is a major ______________ life zone,
terrestrial or aquatic
A Biome is characterized by (2)
- Vegetation type in terrestrial biomes
- The physical environment in aquatic biomes
Aquatic biomes (2)
- Occupy roughly 75% of earth surface
- Are determined by their salinity and other physical factors
Freshwater biomes typically have a salt concentration of ___________.
less then 1%
Standing water:
Lakes and ponds
Flowing water:
Streams and rivers
The _________, named because light is available for photosynthesis, includes algae and plant growth
Photic Zones
The ________ is deeper, and the light levels are too low to support photosynthesis
Aphotic zones
The _______ is at the bottom of all aquatic biomes
Benthic realm
The Benthic realm is made up of __________.
sand and organic and inorganic sediments
Occupied by communities of organisms that are collectively called___________.
benthos
In lakes and large ponds, the communities of plants, algae, and animals are distributed according to the (2)
- depth of water
- distance from shore
Rivers and streams
- are bodies of water flowing in one direction
- generally support quite different communities of organisms than lakes and ponds
Often build dams to control floods, to provide reservoirs for drinking water, or to _______________.
generate hydroelectric power
A _______ is a transitional biome between an aquatic ecosystem and a terrestrial one
Wetlands
Wetlands,support the growth of aquatic plants and are ________ (different kinds of species living in a given area)
Rich in species diversity
Marine biomes Typically have a salt concentration around ____
3%
Marine biomes include ____________________.
Oceans, intertidal zones, coral reef, and esturaies
________ are diverse, ranging from vivd coral reefs to perpetually dark realms in the deepest regions
Marine biomes
As in freshwater biomes, the seafloor is known as the ______________.
Benthic realm
In these sunlight areas photosynthesis by __________(photosynthetic algae and bacteria) and multicellular algae provides energy for a diverse community of animals.
Phytoplankton
The pelagic zone includes (2)
- Zooplankton (free-floating animals, including many microscopic ones)
- Fish and marine mammals
The _______ biome occurs in the photic zone of warm tropical waters, in scattered locations around the globe.
Coral reef
In shallow areas such as the submerged parts of continents are call ____________.
continental shelf
The photic zone (200m) includes _______________.
Pelagic and benthic region
Estuaries (2)
- are transition area between a river and the ocean
- have a saltiness ranging from nearly that of fresh water to that of the ocean
Terrestrial biomes are primarily determined by __________________________.
-temperature and rainfall
Earths global climate pattern are largely that result of (2)
- the input of radiant energy from the sun
- the plants movement in space
Mountains effect climate in two major ways.
- air temperature drops as elevation increases
2. mountains can block the flow of cool, moist air from a coast
Terrestrial ecosystems are grouped into biomes primarily on the _________________.
basis of their vegetation type
Tropical forests occur in equatorial ares, where the temperature is warm, and where days are __________________________.
11-12 hours long year-round
Savannas are dominated by ______________.
grasses and scattered trees
Savannas are _______
warm year-round
Savannas experience rainfall (_____________) with dramatic seasonal variation
roughly 12 to 20 inches per year
Deserts ___________________.
are the driest of all biomes
___________ has a climate that results from cool ocean currents circulating offshore and producing mild, rainy winter and hot, dry summer
Chaparral
Temperature grasslands: _____________.
are mostly treeless
Temperature grasslands (2)
- have 10-30 inches of rain per year
- experience frequent drought and fires
Coniferous forests are dominated by ___________.
cone-bearing evergreen trees
Coniferous include the northern coniferous forest, or ______ the largest terrestrial biome on earth
Taiga
_______________:covers expansive areas of the Arctic between the taiga and polar ice
Tundra
Tundra can be characterized by (3)
- permafrost (permanently frozen subsoil)
- bitterly cold temperatures
- highwinds
________covers the land at high latitudes north of the arctic tundra in the northern hemisphere and Antarctice in the southern hemisphere, only a small portion of these land masses is free of ice or snow, even during the summer
Polar ice
All parts of the biosphere are linked by the__________.
global water cycle
The destruction of tropical rain forests reduces the amount of water vapor in the air, which can affect _________.
rainfall
Pumping large amounts of groundwater to the surface for irrigation _____________________________.
increases the rate of evaporation over land
This can lead to an imbalance of water distribution over biomes,________________.
affecting all life in them
