Chapter 2 Key Terms Flashcards
Ecosystem
a biological community of interacting organisms and their physical environment
Biotic Factor
a living thing, as an animal or plant, that influences or affects an ecosystem
Abiotic Factor
a nonliving condition or thing, as climate or habitat, that influences or affects an ecosystem and the organisms in it
Organism
a form of life composed of mutually interdependent parts that maintain various vital processes.
Species
a form of life composed of mutually interdependent parts that maintain various vital processes.
Population
the assemblage of a specific type of organism living in a given area.
Community
an assemblage of interacting populations occupying a given area.
Habitat
the natural environment of an organism; place that is natural for the life and growth of an organism
Natural Selection
the process by which forms of life having traits that better enable them to adapt to specific environmental pressures, as predators, changes in climate, or competition for food or mates, will tend to survive and reproduce in greater numbers than others of their kind, thus ensuring the perpetuation of those favorable traits in succeeding generations
Evolution
any process of formation or growth; development
Adaptation
any alteration in the structure or function of an organism or any of its parts that results from natural selection and by which the organism becomes better fitted to survive and multiply in its environment
Artificial Selection
a process in the breeding of animals and in the cultivation of plants by which the breeder chooses to perpetuate only those forms having certain desirable inheritable characteristics
Resistance
the act or power of resisting, opposing, or withstanding
Archaea
a group of microorganisms, including the methanogens and certain halophiles and thermoacidophiles, that have RNA sequences, coenzymes, and a cell wall composition that are different from all other organisms: considered to be an ancient form of life that evolved separately from the bacteria and blue-green algae and classified by many biologists as constituting the domain Archaea
Bacteria
ubiquitous one-celled organisms, spherical, spiral, or rod-shaped and appearing singly or in chains, comprising numerous and variously classified phyla: among the inestimable number of species are those involved in fermentation, putrefaction, infectious diseases, and nitrogen fixation
Fungus
any of a diverse group of eukaryotic single-celled or multinucleate organisms that live by decomposing and absorbing the organic material in which they grow, comprising the mushrooms, molds, mildews, smuts, rusts, and yeasts, and classified in the kingdom Fungi or, in some classification systems, in the division Fungi (Thallophyta) of the kingdom Plantae
Protists
any of various one-celled organisms, classified in the kingdom Protista, that are either free-living or aggregated into simple colonies and that have diverse reproductive and nutritional modes, including the protozoans, eukaryotic algae, and slime molds: some classification schemes also include the fungi and the more primitive bacteria and blue-green algae or may distribute the organisms between the kingdoms Plantae and Animalia according to dominant characteristics.
Gymnosperm
a plant that has seeds unprotected by an ovary or fruit. Gymnosperms include the conifers, cycads, and ginkgo.
Angiosperm
a plant that has flowers and produces seeds enclosed within a carpel. The angiosperms are a large group and include herbaceous plants, shrubs, grasses, and most trees.
Invertebrate
an animal lacking a backbone, such as an arthropod, mollusk, annelid, coelenterate, etc. The invertebrates constitute an artificial division of the animal kingdom, comprising 95 percent of animal species and about 30 different phyla.
Vertebrate
an animal of a large group distinguished by the possession of a backbone or spinal column, including mammals, birds, reptiles, amphibians, and fishes
