Almost any chemical can be harmful if

a. it is present in the environment

b. a person is exposed to it repeatedly

c. it's ingested in large amounts

d. a person has never been exposed to it before

Differentiation of cells changes the nucleic information. true false

Which phase of the cell cycle ensures that identical copies of the dna are made for daughter cells?

This is a typical grassland food web. it is also a small picture of an important cycle on earth: the carbon cycle. describe how the carbon gets into this food web. a) bacteria and fungi, the decomposers, recycle carbon from dead organisms. b) carbon is found in the grass and is passed from one level to the next in this food web. eliminate c) all living things give off carbon dioxide as a by-product of respiration and it is released into the atmosphere. d) plants use carbon dioxide as a reactant in photosynthesis, to make usable chemical energy in the form of a sugar.