You are experimenting with cell division on the root cells in an Allium cepa plant in your lab. Before they can divide the DNA must be copied, but the cells seem to only be copying part of the DNA and stopping. Which material might the cell not have enough of to replicate its DNA? A. Triglycerides B. Ribosomes C. Uracil D. Cytosine

it provides an alternative energy pathway for the reaction to proceed.

a catalyst is a substance that speeds up the rate of a chemical reaction but is not consumed during the course of the reaction.

catalysts increase the rate of reaction without being used up. they do this by lowering the activation energy needed. with a catalyst, more collisions result in a reaction, so the rate of reaction increases. different reactions need different catalysts.

a catalyst works by providing an alternative reaction pathway to the reaction product. the rate of the reaction is increased as this alternative route has a lower activation energy than the reaction route not mediated by the catalyst.

her affection for her parents makes her an especially sympathetic character.