5. Abiotic components of the ecosystem include a. Sunlight c. Algae b. Bacteria d. Planktons 6. DDT stands for _______________________. a. dichloroditrichloroethane c. dichlorotriphenylethane b. dichlorodiphenyltrichloroethane d. none of the above 7. Thomas Robert Malthus described the population growth as _________ a. increasing c. decreasing b. exponential d. unchanging 8. A specialist, who studies, collects and analyses data about environmental problems. a. Environmentalist c. Botanist b. Environmental Scientist d. Geologist