Energy and Matter Exchange in the Biosphere 1 Flashcards
What is ecology?
The study of the living and non-living interactions in an ecosystem
What is dynamic equilibrium?
system with constant change, top consumers are most sensitive
What are the levels of organization?
Biosphere, ecosystem, community, population, multicellular organism, organ system, organ
What is the biosphere? 3 parts of the biosphere?
part of earth inhabited by organisms, lithosphere (earth’s crust, outer solid part of earth), hydrosphere (water portion of earth’s crust), atmosphere (gasses that surround the earth)
What are the at-risk categories?
Extinct
Extirpated (no longer exist in one part of country)
Endangered (close to extinction in all parts of country)
Threatened (species likely to become endangered)
Special Concern (species at risk, low/declining numbers)
What are indicator species?
species sensitive to small changes in environmental conditions, early warning system for health of an ecosystem, amphibians (2 ecosystems/food chains, aquatic and terrestrial)
Describe the role of organisms
sun, autotrophs (producers, produce their own food, make 99% of all biomass), heterotrophs (tertiary, secondary, primary consumers), decomposers (heterotrophs feed on detritus)
What is a trophic level? What is the first trophic level? What is the original energy source?
How far an organism is from the original source, plants, sun
What does the food chain show?
step sequence of who eats who in biosphere, shows energy transfers and cycling of matter in biosphere
What do food webs always start with?
autotrophs
What is chemosynthesis
producers (chemoautotrophs) make food with water, carbon dioxide and an energy source other than the sun (ammonia, sulfur))
How do organisms use energy stored in their food?
cell resp
What limits the number of trophic levels?
energy flows in one direction, only 10% energy transferred to next trophic level, 90% lost to thermal energy released by metabolism (cell resp)
What are the two laws of thermodynamics?
energy can be changed from one form to another but cannot be created or destroyed, any energy change results in loss of energy as heat
longer food chains…
less energy for top consumer
What are ecological pyramids?
visually rep energy flow in food chains, pyramid of biomass (total dry mass of all living matter, first trophic level largest), pyramid of energy (energy flowing in level, rep by J/KJ, proportional), pyramid of numbers (total number of organisms (4th trophic tiny)
What type of system is a biosphere?
closed system, energy can move in and out, matter does not enter or leave, matter must be recycled, bio-geochemical cycles
What are bio-geochemical cycles?
cycle of transferring nutrients from environment to organism to environment, hydrological, carbon, oxygen, nitrogen, phosphorous
What are the 2 sources of freshwater?
Ground water (rain seeps into soil), surface water (precipitation collects above ground in lakes and rivers, glaciers)
What is percolation? leaching? water table?
movement of liquid through porous material, removal of soluble minerals by percolation, top level of region below ground saturated with water
What are the types of acid rain?
Wet acid deposition (SO2 and NOx from factory and automobile emissions (fossil fuel burning) mixes with water in sky and fall as rain), dry acid deposition (same source, fall as solid)
What is the carbon cycle?
cycle of matter where c atoms move from inorganic (CO2) form to organic (nutrients, peat) form, back to inorganic, reservoirs
What is a mesocosm?
experiment, mini ecosystem
What are human impacts on the carbon cycle?
burning fossil fuels, deforestation, CO2 added to atmosphere, ocean can only absorb so much CO2
What is the oxygen cycle?
oxygen cycles between living things and the atmosphere (photosynth and cell resp), stored in atmosphere, water, rocks
Describe the nitrogen cycle
needed for proteins and DNA, nitrogen fixation (nitrogen fixing bacteria, lightning, legumes, N gas to ammonia), nitrification (ammonia NH3, to nitrite NO2 to nitrate NO3), decomposition (detritus to ammonia), denitrification (nitrate to N gas), assimilation (change nutrient to different molecule)
Describe the phosphorous cycle
nutrient required by all living things, DOES NOT INVOLVE ATMOSPHERE ANAEROBIC, short term cycle (phosphates inw ater enter food chain through producers, return to soil decomp, phos absorbed by plants, used by photosyn, eaten), long term cycle (phos dissolve in water, erosion carry to strems turn into land)
What is eutrophication?
oligotrophic lakes fill with nutrients become land
