Chapter 2 Key Terms

Question 1

Ecosystem

Answer 1

a biological community of interacting organisms and their physical environment

Question 2

Biotic Factor

Answer 2

a living thing, as an animal or plant, that influences or affects an ecosystem

Question 3

Abiotic Factor

Answer 3

a nonliving condition or thing, as climate or habitat, that influences or affects an ecosystem and the organisms in it

Question 4

Organism

Answer 4

a form of life composed of mutually interdependent parts that maintain various vital processes.

Question 5

Species

Answer 5

a form of life composed of mutually interdependent parts that maintain various vital processes.

Question 6

Population

Answer 6

the assemblage of a specific type of organism living in a given area.

Question 7

Community

Answer 7

an assemblage of interacting populations occupying a given area.

Question 8

Habitat

Answer 8

the natural environment of an organism; place that is natural for the life and growth of an organism

Question 9

Natural Selection

Answer 9

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

Question 10

Evolution

Answer 10

any process of formation or growth; development

Question 11

Adaptation

Answer 11

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

Question 12

Artificial Selection

Answer 12

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

Question 13

Resistance

Answer 13

the act or power of resisting, opposing, or withstanding

Question 14

Archaea

Answer 14

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

Question 15

Bacteria

Answer 15

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

Question 16

Fungus

Answer 16

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

Question 17

Protists

Answer 17

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.

Question 18

Gymnosperm

Answer 18

a plant that has seeds unprotected by an ovary or fruit. Gymnosperms include the conifers, cycads, and ginkgo.

Question 19

Angiosperm

Answer 19

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.

Question 20

Invertebrate

Answer 20

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.

Question 21

Vertebrate

Answer 21

an animal of a large group distinguished by the possession of a backbone or spinal column, including mammals, birds, reptiles, amphibians, and fishes