Most ocean food chains depend on phytoplankton as primary producers. Where in the ocean do phytoplankton live? A. throughout all ocean waters, because phytoplankton can tolerate a wide range of temperature and light conditions
B. within about 200 meters of the ocean shoreline, because phytoplankton depend on nutrients that wash into the water from land
C. within about 200 meters of the ocean surface, because phytoplankton require light to survive
D. attached to shells along the ocean floor, because phytoplankton cannot float

4.) metal

"-the movement of carbon from the nonliving environment into living things and back to the environment

-carbon is the essential component of proteins, fats, and carbohydrates (which make up all organisms)

-carbon exists in air, water, and living organisms

-producers convert carbon dioxide in the atmosphere into carbohydrates during photosynthesis

-bacteria in the atmosphere cycles through the system in filtration units

-in cellular respiration, carbon is released back into the atmosphere as carbon dioxide

-some carbon is stored in limestone (forming one of the largest "carbon sinks" on earth)

-largest carbon reservoir on earth= limestone

-carbon stored in the bodies of organisms as fat, oils, or other molecules may be released into the soil or air when the organism dies

-this may form deposits of coal, oil, or natural gas (fossil fuels, which increased the atmospheric carbon dioxide)

-fossil fuels store carbon left over from bodies of organisms that died millions of years ago

-they are located in the surface of earth, deep within the earth and beneath the ocean floor."    

during the process of dna replication, brdu can replace thymidine and incorporate into the newly synthesized dna, cell proliferation thus can be reflected in the extent of brdu incorporation.

i believe the answer would be b. hope it : )

d. planting trees

the trees take in carbon to make oxygen.