What is true of a catalyst? a. it is not consumed by the reaction. b. it is a product of a chemical reaction. c. it is a reactant in a chemical reaction. d. it provides the energy needed for the reaction.

How can scientists test their ideas about the origin of the universe if they can't physically interact with or study?

Which part of the cell is affected by the movement of molecules through diffusion, osmosis and active transport?

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.