Which of the following statements about cell differentiation is true? A. Cell differentiation occurs only in adult organisms
B. Cell differentiation cannot be affected by the environment
C. Cells differentiate because the dna in each cell of an organism is different
D. Cells differentiate because different areas of the dna are activated in each cell type.

Variety of living organisms; includes genetic, species, and ecological types.

Body temperature is tightly regulated in mammals for example when external temperatures drop too much the body of a mammal responds by in order to its core temperature?

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.