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Ch 21 Living Things

organism living thing
biotic factors living parts of a habitat
abiotic factors non living parts of a habitat - water, sunlight, temperature, soil, oxygen
species group of organisms that are physically similar and can mate with each other to produce offspring
population all the members of one species in a particular area
community all the different populations that live together in an area
ecosystem the community of organisms that live in a particular, along with the non-living surroundings
ecology the study of how living things interact with each other and with their environment
estimate an approximation of a number, based on reasonable assumptions
birth rate the number of births in a population in a certain amount of time
death rate the number of deaths in a population in a certain amount of time
immigration moving into a population
emigration leaving a population
population density the number of individuals in an area of a specific size
carrying capacity the largest population that an area can support
limiting factor an environmental factor that causes a population to decrease - water, food, space, weather
natural selection a characteristic that makes an individual better suited to its environment is this process
adaptation behaviors or physical characteristics that allow organisms to live successfully in their environments
niche the role of an organism in its habitat
competition struggle between organisms to survive as they attempt to use the same limited resources
predation interaction in which one organism kills another for food
predator the organism that does the killing
prey the organism that is killed and eaten
symbiosis close relationship between two species that benefits at least one of the species
parasite an organism living in or on another organism and harming it
host the organism affected negatively by a parasite
Created by: carlocrew