Which of the following is true of the composition of all materials?

A.
All materials are made up of large parts that can only be seen by the human eye.
B.
All materials are made up of living cells.
C.
All materials are made up of only one part.
D.
All materials are made up of smaller parts that cannot be seen without magnification.

1. an enzyme is considered a(n) because it speeds up a chemical reaction without being used up.2. in a catalyzed reaction, a reactant is often called a(n) . an enzyme is specific because the shape of its matches only particular reactants.4. an enzyme speeds up reactions by lowering the . the between an active site and its substrate often strains bonds and the reaction proceed.6. a( , which is often a vitamin, binds to an enzyme and plays a role in catalysis.7. high temperatures or changes in ph can an enzyme, causing it to lose its shape and biological activity.