Page 102 - The Miracle in the Cell
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THE MIRACLE IN THE CELL
ENZYME ENZYME
Molecule
Molecule to after under-
be changed going change
Figure 5.4
This diagram shows the perfect three-dimensional fit between an enzyme
(hexokinase) and the substance it acts on. The hexokinase enzyme converts
ATP into ADP, then ADP into ATP. In the first box, the enzyme closes in on
the molecule it's going to act upon. In the second box, different parts of the
enzyme separate, and the molecule is released, having been changed into its
new state.
Affected molecules
Enzyme Enzyme Enzyme
Figure 5.5 Section subjected to change
An enzyme joins two different molecules together, thereby forming a new mol-
ecule. The reaction between the molecules and the enzyme is very short, and it
comes out unchanged at the end of the reaction, ready to act on new molecules.
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