a long-term and physically close relationship between two organisms from different species in which at least one organism benefits; commensalism, mutualism, and parasitism are all symbiotic relationships
Symbiosis
an organism that can capture energy from the sun or from chemicals and store it; also called autotroph
Primary producer
a diagram of feeding relationships and energy flow showing the paths by which nutrients and energy pass from organism to organism as one consumes another
Food web
biological evolution that occurs by chance
Genetic drift
a human-controlled process to produce individuals with certain traits
Artificial selection
a relationship between two organisms from different species in which one benefits and the other is unaffected
Commensalism
an organism that eats plants
Herbivore
an organism (e.g., a fungus or bacterium) that breaks down nonliving matter into simple parts that can then be taken up and reused by primary producers
Decomposer
the degree to which an organism can reproduce successfully in its environment
Fitness
the total amount of living tissue in a trophic level
Biomass
the process by which individuals of one species (the predators) hunt, capture, and feed on individuals of another species (the prey)
Predation
the process by which primary producers use sunlight to convert carbon dioxide and water into sugars, releasing oxygen
Photosynthesis
a linear series of feeding relationships
Food chain
a sequence of DNA that codes for a particular trait
Gene
the process by which bacteria use energy stored in bonds of hydrogen sulfide to convert carbon dioxide and water into sugars
Chemosynthesis
a relationship between two organisms from different species in which one organism (the parasite) depends on the other (the host) for nourishment or some other benefit
Parasitism
the act of feeding on a plant
Herbivory
an organism (e.g., a millipede or soil insect) that scavenges the waste products or dead bodies of other community members
Detritivore
a heritable trait that increases the likelihood of an individual’s survival and reproduction
Adaptation
the process by which organisms use oxygen to release the chemical energy of sugars, producing carbon dioxide and water
Cellular respiration
a relationship between two organisms from different species in which both organisms benefit
Mutualism
an animal that eats both plants and animals
Omnivore
an organism that relies on other organisms for energy and nutrients; also called heterotroph
Consumer
an accidental change in DNA
Mutation
a species that has a strong or wide-ranging impact on a community
Keystone species