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1 Introduction

Figure 1.28: Example of a titration curve to determine the buffer capacity of acetic acid.

usually done by having the cell-solution (cytosol) have a certain buffer capacity, so that

acids and bases only change the pH slightly when reacting (Figure 1.28).

In Organic Chemistry, when it is necessary to increase the energy of a starting ma-

terial the reaction is usually heated. This is obviously not possible in a cell. In Biochem-

istry, the compound is therefore reacted with the “energy-storage molecule” adenosine

triphosphate (ATP), and thus a high-energy bond to a phosphate is added to the molecule

(Figure 1.29). When this phosphate is then exchanged with a different functional group,

Figure 1.29: Adenosine triphosphate (ATP) is used as the energy storage molecule in the cell.