Evir. Science Exam #2 Flashcards
The Earth is materially ____ but energetically _____
closed, open
Cycles can be in the
hydrosphere, atmosphere, lithosphere, or biotic organisms
Residence Time
the amount of time the nutrients stay in the sink
Photosynthesis Equation
H2O + CO2 ➡ O2 + C6H12O6
Cellular Respiration Equation
O2 + C6H12O6 ➡ H2O + CO2
Why does cellular respiration need oxygen?
To break the bonds
The purpose of cellular respirations, with the carbon cycle?
To release the chemical energy of a sugar molecule
Order of the Nitrogen Cycle
- Atmosphereic Nitrogen (N2)
- Nitrogen Fixation
- Ammonia (NH3)
- Nitrification
- Nitrate (NO3-)
- Denitrification
Deforestation affect which cycle
Carbon cycle
Deforestation affects which cycle(s)
Carbon cycle
Fossil Fuel Combustion affects which cycle(s)
Carbon cycle and Nitrogen cycle
Fertilization affects which cycle(s)
Nitrogen cycle and Phosphorous cycle
Mining affects which cycle(s)
Phosphorous cycle
Nitrogen Cycle is need to
make protein and nucleic acids
Plants can’t use nitrogen directly from the atmosphere so it must be converted into a usable form by what process
Nitrogen Fixation
Nitrogen Fixation
Bacteria converts atmospheric nitrogen into ammonium
N2 ➡ NH4+
Assimilation
Ammonium is taken up by plants and consumed by animals to make biological molecules (no bacteria used)
Nitrification
Nitrifying bacteria converts ammonium into nitrates
NH4+ ➡ NO3+ (Adds oxygen)
Denitrification
Denitrifying bacteria converts nitrates back to atmospheric nitrates back to atmospheric nitrogen gas
NO3- ➡ N2 (Takes oxygen away)
In the Nitrogen Cycle, which step does not involve bacteria?
Assimilation
The Phosphorus Cycle is needed by
all organisms to make DNA
Which cycle does not have an atmospheric component?
Phosphorus Cycle
Organize the 6 sizes of life from largest to smallest
Biosphere, Biome, Ecosystem, Community, Population, Individual
What are the 3 main types of biomes?
Terrestrial, marine, and Freshwater
Biomes are defined as distinctive types of ecosystems determined by:
Climatic factors such as temperature and precipitation
What are the 3 zones?
Polar, Temperate, and Tropical
Mountains and coastlines are
geographic features
Range of Tolerance
the range of a limiting factor within which a species can survive and reproduce
Range of tolerance is a
population concept
Limiting Factor
the critical resource whose availability determines species population size distribution
Population
all individuals of a species which live in the same geographic area and interbreed
Range
geographic area where a species or one of its populations can be found
Population Distribution
location of spacing of individuals within their range
Clumped Distribution
Individuals found in groups within the habitat
(Seen in more social species)
Random Distribution
Individuals spread out irregularly
(Wind-blown seeds that germinate where they land)
Uniform Distribution
Individuals spaced evenly due to territorial behavior or other mechanisms
(Seen like in farming)
Population Density
the number of individuals per unit area
If the population density is too low
it is hard to find mates
If the population density is too high
it increases competition, spread of diseases, and fighing
Growth Rate Equation
Birth Rate - Death Rate = Growth Rate
Annual Population Growth Equation
b/N x 100
Biotic Potential
when a population will reach its maximum per capita rate of increase without environmental limits
Exponential Growth occurs
in a population when there are no limits and is typically seen when a species enters a new environment or with an influx of new resources (J-shaped graph)
Carrying Capacity (K)
maximum population size a particular environment can support indefinitely which is determined by growth factors and can increase or decrease as resource availability changes
Logistic Population Growth
population growth rate slows as the size approaches the carrying capacity (S-shaped graph)
Density-Dependent Factors
effects increase as populations grow such as disease, competition, and predation
Density-Independent Factors
affect a population regardless of its size, and can decrease the population such as storms, fires, flooding, and an avalanche
r-selected species
adapt well to unpredictable environments; has a high biotic rate; can increase or decrease quickly in response to environmental changes
Which selected species has sudden population growth that can cause overshoot & crash or boom-bust cycles?
r-selected species
K-selected species
reproduce slowly; has a lower biotic potential; more likely to have a stable population size close to carrying capacity; less adaptable in the face of environmental change
Top-Down:
Control is from predators (high on the food chain)
Bottom-Up:
Control is from the bottom of the food chain
Community Ecology
the study of all the species and how they interact with each other, which includes human interaction as well
Energy
the foundation of every ecosystem; captured through photosynthesis; passed from organism to organism through food chains
Trophic Levels
represent feeding levels in a food chain; organized on what consumers eat; some feed at more than 1 trophic level
Why are there seldom more than 5 trophic levels?
Only a small percentage of energy is passed which leaves very little of the original energy captured by the producers
Food Webs
food chains linked together shows connections in the community more complex food webs provide greater stability
Niche Generalist
occupies a broad niche and can utilize a wide variety of resources
Niche Specialist
very specific habitat or resource requirements restrict where it can live
Competitive Exclusion Principle
one species excludes another from a portion of the same niche as a result of competition for resources
Species Richness
the total number of different species in a community
Which one of the following cycles currently has the greatest impact on global climate change?
Carbon Cycle
Which of the following latitudes will have an arid climate?
30 North
Which one of the following does NOT increase atmospheric carbon dioxide levels?
Producers
Denitrification involves the conversion of nitrate into _____ by bacteria, which returns nitrogen to the _____.
nitrogen gas
atmosphere
What is one of the most extreme K-selected species?
Florida Panther
Why doesn’t exponential growth continue indefinitely?
Available resources will eventually become scarce as more individuals use them.
Under what condition do distinct populations of gray wolves occur within a geographic range?
when the species’ range is broadly distributed
What is an example of a factor affecting the population distribution of a species?
Topography
Mutualism
A symbiotic relationship between individuals of two species in which both parties benefit
Species Evenness
relative abundance of each individual species
Keystone Species
Impacts its community more than its community would crumble
Symbiosis
Close biological or ecological relationship between 2 species
Parasitism
Organisms live and feed in or on other organisms, usually parasite does not killl its host, does harm host and may contribute to its death (+, -)
What is an example of mutualism?
Flowers and bees
What is an example of parasitism?
Mosquitoes and mistletoe
Commensalism
1 species benefits, the other is unaffected (+, 0)
What is an example of commensalism?
Whales and Barnacles
Predation
Organisms hunt, kill, and consume prey, many predators hunt various species, and have adaptations to help them hunt (+, -)
Competition
Interaction among organisms vying for the same limited resourec in an ecosystem (- , -)
Intraspecific
between individuals of the same species in a population
Interspecific
between individuals of different species in a population
Resource Partitioning
Division of resources so potential competitors may coexist
Trophic Cascades
Changes in abudances of organisms at 1 trophic level can influence energy flow at multiple trophic levels
Ecosystem Engineer
A species that physically reorders the habitat
Biome
an area classified according to the species that live in that location
Biosphere
made up of the parts of Earth where life exists
Ecosystem
a geographic area where plants, animals, and other organisms, as well as weather and landscape, work together to form a bubble of life
What 2 factors determine what a biome is characterized as?
Temperature and Precipitation
Tundra
- Above 60°N and S
- Growing Season: < 3 months
- Rainfall: 100-500 mm/yr
- Temperature: < 5°
- Cold winters/ short summers
- Migrating herbivores, small mammals, predatory birds, polar bears, snow owls, caribou
- Penguins and Seals in the South Pole
- Moss and Lichen
Boreal Forest
- Above 60°N and S
- Growing Season: < 4 months
- Rainfall: 500-1,500 mm/yr
- Cold, dry winters
- Large mammals, small animals, migrating birds
- Bears, rabbits, wolves
- Conifers and Eastern Larch (drought resistant
Temperate Forest
- 30° to 60° N and S
- Growing Season: From the last and 1st hard frost
- Rainfall: 750 -1,000 mm/yr
- Temperature: 5° - 20° C
- Deer, bears, and small woodland animals
- Black bears, fox, skunk squirrels, songbirds
- Topsoil rich in organic material
Grassland
- 30° to 60° N and S
- Rainfall: 250-750 mm/yr
- Periodic fires
- 90% altered into agricultural lands
- Grazing animals, small mammals reptiles, birds of prey
- Snakes, prairie dogs, antelope, hawks
- Limited tree growth
- Richest organic soil horizon
Mediterranean Scrub
- By the Ocean (random)
- Rainfall: 250-500 mm/yr
- Mild, moist winters and hot, dry summers
- Thin soil, not fertile
- Dense growth of evergreen shrubs
- Stoney Leafed plants
Parts of an environmental gradient
Zone of Stress and Zone of Optimal Range
What’s another name for a grassland?
Steppes
What are the 3 biomes that are fire adapted?
Savannas, Deserts, and Grasslands
Savanna
- Extends to 25° N/S
- Rainfall: 760-1,200 mm/yr
- Warm, constant temperature
- Adapted to periodic fires
- Low nutrient soil from leaching
- Zebras, lions, hyenas, giraffes, elephants, hippos, koalas, kangaroos
Tropical Rainforest
- 0 to 25° N/S
- Growing Season: year-round
- Rainfall: < 2,000 mm/yr
- Warm, constant temperatures
- Nutrient-poor soil
- Tigers, sloths, toucans, parrots, monkeys orangutans, lots of beetles, lots of amphibians
