| 9654804005 | Population | a localized group of individuals of the same species that can interbreed, producing fertile offspring |  | 0 |
| 9654804006 | Community | all the organisms that inhabit a particular area; as assemblage of populations of different species living close enough together for potential interaction |  | 1 |
| 9654804007 | Ecosystem | all the organisms in a given area as well as the abiotic factors with which they interact |  | 2 |
| 9654804008 | Biotic | pertaining to the living organisms in the environment |  | 3 |
| 9654804009 | Abiotic | nonliving; referring to physical and chemical properties of an environment |  | 4 |
| 9654804010 | Biosphere | the entire portion of earth inhabited by life; the sum of all the planet's ecosystems |  | 5 |
| 9654804011 | Niche | the sum of a species' use of the biotic and abiotic resources in its environment | | 6 |
| 9654804012 | Clumped Distribution | individual aggregated patches, some organisms group together where food is abundant |  | 7 |
| 9654804013 | Uniform Distribution | evenly spaced, some organisms maintain evenly distributed spacing to avoid aggressive interactions between neighbors |  | 8 |
| 9654804014 | Random Distribution | unpredictable spacing, some plants grow in random groups if their seeds were windblown across an area |  | 9 |
| 9654804015 | Population Ecology | the study of populations in relation to their environment, including environmental influences on populations, on population density and distribution, age structure, and variations in population size | | 10 |
| 9654804016 | Birth Rate | rate of annual birth within a population | | 11 |
| 9654804017 | Death Rate | rate of annual death within a population | | 12 |
| 9654804018 | Sex Ratio | ratio of females to males within a population | | 13 |
| 9654804019 | Age Structure | the relative number of individuals of each age in a population | | 14 |
| 9654804020 | Immigration Rate | the rate of influx of new individuals INTO a population from other areas | | 15 |
| 9654804021 | Emigration Rate | the rate of movement of individuals OUT of a population | | 16 |
| 9654804022 | Carrying Capacity | the maximum population size that can be supported by the available resources, (symbolized by K) |  | 17 |
| 9654804023 | Density Dependent | any characteristic that varies according to an increase in population density | | 18 |
| 9654804024 | Exponential Growth | growth of a population in an ideal, unlimited environment, (represented by a J-Shaped curve when population size is plotted over time) |  | 19 |
| 9654804025 | Logistical Growth | population growth that levels off as population size approaches carrying capacity | | 20 |
| 9654804026 | K-Selected | stabilize around carrying capacity, have fewer offspring later in life, mature later, live longer and invest more parental care | | 21 |
| 9654804027 | R-Selected | reside in unstable environment, have many offspring early in life, mature earlier, shorter life span, no parental care | | 22 |
| 9654804028 | Survivorship Curve | the plot of the proportion or numbers in a cohort still alive at each age | | 23 |
| 9654804029 | Type I Surivorship Curve | low death rates during early/middle life then increase among older age groups (humans) | | 24 |
| 9654804030 | Type II Surviorship Curve | constant death rate over the organism's life span | | 25 |
| 9654804031 | Type III Surviorship Curve | very high death rates for the young and then declines for those few individuals that survive the early period (insects) | | 26 |
| 9654804032 | Symbiosis | an ecological relationship between organisms of two different species that live together in direct and intimate contact | | 27 |
| 9654804033 | Commensalism | a symbiotic relationship in which one organism benefits but the other is neither helped nor harmed | | 28 |
| 9654804034 | Mutualism | a symbiotic relationship in which both participants benefit | | 29 |
| 9654804035 | Parasitism | a symbiotic relationship in which one organism (the parasite) benefits at the expense of another (the host) by living either within or on its host | | 30 |
| 9654804036 | Intraspecific Competition | interactions between the same species competing for resources | | 31 |
| 9654804037 | Interspecific Competition | competition for resources between individuals of two or more species when resources are in short supply | | 32 |
| 9654804038 | Predation | an interaction between species in which one species (the predator) eats the other (the prey) | | 33 |
| 9654804039 | Aposematic Coloration | the bright coloration of animals with effective physical or chemical defenses that acts as a warning to predators | | 34 |
| 9654804040 | Batesian Mimicry | a type of mimicry in which a harmless species look like a species that is poisonous or harmful to predators | | 35 |
| 9654804041 | Cryptic Coloration | camouflage that makes a potential prey difficult to spot against its background | | 36 |
| 9654804042 | Mullerian Mimicry | a mutual mimicry by two unpalatable species | | 37 |
| 9654804043 | Pioneer Species | the first species to colonize previously disrupted or damaged ecosystems, beginning a chain of ecological succession that ultimately leads to a more biodiverse steady-state ecosystem | | 38 |
| 9654804044 | Climax Community | in a community of organisms in a specific area there is one state of equilibrium controlled solely by climate | | 39 |
| 9654804045 | Succession | the process by which the structure of a biological community evolves over time | | 40 |
| 9654804046 | Primary Succession | a type of ecological succession that occurs in an area where there were originally no organisms present and where soil has not yet formed | | 41 |
| 9654804047 | Secondary Succession | a type of succession that occurs where an existing community has been cleared by some disturbance that leaves the soil or substance intact | | 42 |
| 9654804048 | Photoautotrophs | an organism that harnesses light energy to drive the synthesis of organic compounds from Carbon Dioxide (CO2) | | 43 |
| 9654804049 | Chemoautotrophs | an organism that needs only CO2 as a carbon source but obtains energy by oxidizing inorganic substances | | 44 |
| 9654804050 | Herbivore | an animal that eats mainly plants or algae | | 45 |
| 9654804051 | Carnivore | an animal that mainly eats other animals | | 46 |
| 9654804052 | Detritivore | a consumer that derives its energy and nutrients from nonliving organic material such as corpses, fallen plant material, and the wastes of living organism (a decomposer) | | 47 |
| 9654804053 | Food Chain | the pathway along which food energy is transferred from trophic level to trophic level, beginning with producers | | 48 |
| 9654804054 | Food Web | the interconnected feeding relationships in an ecosystem | | 49 |
| 9654804055 | Trophic Levels | the positions organisms occupy in a food chain |  | 50 |
| 9654804056 | Secondary Consumer | a carnivore that eats herbivores | | 51 |
| 9654804057 | Primary Consumer | a herbivore; an organism that eats plants or other autotrophs | | 52 |
| 9654804058 | Biogeochemical Cycles | any of the various chemical cycles, which involve both biotic and abiotic components of ecosystems | | 53 |
| 9654804059 | Carbon Cycle | forming the framework of organic molecules, photosynthesis & cellular respiration circulate this nutrient | | 54 |
| 9654804060 | Phosphorus Cycle | cycling of this nutrient through geologic processes such as erosion and sedimentation | | 55 |
| 9654804061 | Nitrogen Cycle | this nutrient is converted to compounds that can be assimilated by plants then returned in gas form to the atmosphere; all processes rely on bacteria | | 56 |
| 9654804062 | Nitrogen Fixation | the conversion of atmospheric nitrogen to ammonia | | 57 |
| 9654804063 | Denitrification | process where bacteria use nitrates in their metabolism instead of oxygen releasing nitrogen gas then into the atmosphere | | 58 |
| 9654804064 | Water Cycle | this nutrient cycle involves evaporation from the earth & transpiration from plants and falls then by precipitation back down to the earth to begin the cycle again | | 59 |
| 9654804065 | Age Structure Diagrams | a visual representation of the relative number of individuals of each age in a population | | 60 |
| 9654804066 | Competitive Exclusion Principle | the concept that when populations of two similar species compete for the same limited resources, one population will use the resources more efficiently and have a reproductive advantage that will eventually lead to the elimination of the other population | | 61 |
| 9654804067 | Resource Partitioning | the division of environmental resources by coexisting species such that the niche of each species differs by one or more significant factors from the niches of all the coexisting species | | 62 |
| 9654804068 | Zero Population Growth (ZPG) | a period of stability in population size, when the per capita birth rate and death rate are equal | | 63 |
| 9654804069 | Gross Primary Productivity (GPP) | the total primary production of an ecosystem | | 64 |
| 9654804070 | Net Primary Productivity (NPP) | the gross primary production of an ecosystem minus the energy used by the producers for respiration | | 65 |
| 9654804071 | Keystone Species | a species that is not necessarily abundant in a community yet experts strong control on community structure by the nature of its ecological role or niche | | 66 |
| 9654804072 | Bottom-up Model | a model of community organization in which mineral nutrients influence community organization by controlling plant or phytoplankton numbers, which in turn control herbivores, which in turn control predator numbers | | 67 |
| 9654804073 | Top-down Model | a model of community organization in which predation influences community organization by controlling herbivore numbers, which in turn control plant or phytoplankton numbers, which in turn control nutrient levels; also called the trophic cascade model | | 68 |
| 9654804074 | Biological Magnification | a process in which retained substances become more concentrated at each high trophic level in a food chain | | 69 |
| 9654804075 | Decomposers | organisms that absorb nutrients from nonliving organic material such as corpses, fallen plant material, the wastes of living organisms and converts them into inorganic forms; a detritivore | | 70 |
| 9654804076 | Eutrophication | a process by which nutrients, particularly phosphorus and nitrogen, become highly concentrated in a body of water, leading to increased growth of organisms such as algae or cyanobacteria | | 71 |
| 9654804077 | Fundamental Niche | the niche potentially occupied by that species | | 72 |
| 9654804078 | Realized Niche | the portion of the fundamental niche that a species actually occupies in the environment | | 73 |
| 9654804079 | Invasive Species | a species often introduced by humans, that takes hold outside its native range | | 74 |
| 9654804080 | Altruism | behavior that increases fitness of another individual but decreases their own fitness | | 75 |
| 9654804081 | Kin selection | enhancing the reproductive success of one's relatives | | 76 |
| 9654804082 | Nitrification | ammonia is converted to nitrates and nitrites | | 77 |
| 9654804083 | Ammonification | decomposers convert organic nitrogen to ammonia | | 78 |
| 9654804084 | Classical conditioning | association between neutral stimulus and natural response (ex: dogs salivating to sound of bell ringing) | | 79 |
| 9654804085 | Operant conditioning | trial and error learning; making associations between behavior and a reward or punishment | | 80 |
| 9654804086 | Communication | tactile, visual, auditory and chemical means of relaying messages to other members of ones species | | 81 |
| 9654804087 | Taxis | directed movement towards or away from a stimulus | | 82 |
| 9654804088 | Kinesis | movement in response to a stimulus that is not directional | | 83 |
| 9654804089 | Fixed Action Pattern | a sequence of unlearned actions that are unchangable and often carried to completion | | 84 |
| 9654804090 | Density dependent factor | factor that affects population based on size (disease, predation etc) | | 85 |
| 9654804091 | Density independent factor | factor that affect population regardless of size (weather, humans etc) | | 86 |
| 9654804092 | Species diversity | variety of organisms in a community | | 87 |
| 9654804093 | Species richness | the number of different species in a community | | 88 |
| 9654804094 | Relative abundance | evenness of distribution of individuals among species in a community | | 89 |
