Biology CH 42.

• The principle of relative abundance is the percent composition of an organism of a particular kind relative to the total number of organisms in an area.
• 1st Law of Thermodynamics: Energy cannot be created or destroyed since energy is stored in organic molecules equal to solar energy intercepted plants minus the amount reflected and dissipated as heat.
• 2nd Law of Thermodynamics: Every exchange of energy increases the entropy of the universe. Some energy is lost in heat, each unit of heat eventually leaves. Ecosystem depend on heat and would be lost w/o it
• detritivore: A consumer that derives off of energy and nutrients from non-living organisms
• Detritus: dead organic matter
• The difference between Chemical Cycling and Energy flow is that energy flows through ecosystem does not cycle for long periods of time, since energy is flowing, losing it's heat dissipating
• Light energy is converted to chemical energy in the form of organic compounds.
• Certain wavelengths are absorbed by photosynthetic pigments, while the rest is transmitting or reflected, or lost as heat.
• Gross Primary Production (GPP)- The amount of energy from light
• Net Primary Production (NPP): equal to the GPP minus the energy used by primary producers (autotrophs) ^note(Ra) is autotrophs
• Net Primary Production is the new biomass added in a give amount of time.
• Gross Primary Production: The total primary production of an ecosystem
• Net Primary Production: The gross primary production of an ecosystem minus the energy used by the producers for respiration.
• NPP should be about one half of GPP
• NPP is the key measurement because it represents the storage of chemical energy that will be available to consumers in the ecosystem.
• Net Ecosystem Production: The gross primary production of an ecosystem minus the energy used by all autotrophs and heterotrophs for respiration.
• NPP is the key measurement because it represents the storage of chemical energy that will be available to consumers in the ecosystem.
• Eutrophication: A produces by which nutrients, particularly phosphorus and nitrogen, become highly centered in a body of water, leading to increased growth of organisms such as algae or cyanobacteria.