1.3 Nanoscale Reactions

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Figure 1.27: An example of a radical reaction (radical polymerization of polyethylene).

and modulating the activity of the enzyme itself. In Organic Chemistry, reactions have

to be regulated by environmental factors such as solvent polarity or temperature. And,

in almost all cases, the products of Organic Chemistry reactions have to be purified from

side products.

One of the most important reactions in both Organic and Biochemistry is the reac-

tion of an acid or a base with water or with each other. The reason for that is first of all

that acids and bases change the pH of the aqueous solution. In a cell, this could easily be

deadly; remember, cells and organs have to work within the tight confines of homeosta-

sis. Conversely, the pH of the environment changes the reactivity of the molecules in a

solution by changing the charge of the molecules, and with that their nucleophilicity or

electrophilicity. Since most reactive functional groups are at least somewhat acidic or

basic, this interplay has to be taken into account and tightly managed. In the cell that is