Ecology Test #2

the struggle between organisms to survive in a habitat with limited resources

full range of physical and biological conditions in which an organism lives and the way in which the organism uses those conditions

a relationship in which two different organisms live in close association with each other

symbiotic relationship between two organisms in which one organism benefits & the other is unaffected

symbiotic relationship in which both species benefit from the relationship

first species to populate an area during primary succession

Small birds eat insects from the backs of rhinoceroses. The birds obtain food, and the rhinoceroses eliminate biting insects from their skins. Which ecological relationship is being represented?

• commensalism

• mutualism

• parasitism

• predation

DNA is made up of sugars, phosphate groups, and nitrogen bases. Which process is NOT involved in moving a nitrogen atom into the DNA of a cow?

• decomposition of plant matter

• digestion of plant matter by the cow

• nitrogen fixation in root nodules of a plant

• conversion of nitrate to nitrogen gas by denitrifying bacteria

Which statement describes the function of producers in Earth's biogeochemical cycles?

• producers add nitrogen to the atmosphere and remove oxygen to the atmosphere

• producers remove carbon dioxide from the atmosphere and add oxygen to the atmosphere

• producers add carbon dioxide to the atmosphere and remove oxygen from the atmosphere

• producers remove nitrogen from the atmosphere and add carbon dioxide to the atmosphere

Water changes phase over the course of the water cycle. Which process in the water cycle most directly results from condensation?

• the formation of clouds and precipitation

• the flow of runoff into a river and ocean

• the movement of water from plants to the atmosphere

• the entrance of precipitation into groundwater reservoirs