Final answer:
Enzymes are biological catalysts primarily made of proteins that speed up chemical reactions by lowering the activation energy. They are specific to their substrates and sometimes require cofactors to function properly. Contrary to the question's second option, enzymes reduce rather than increase activation energy.
Step-by-step explanation:
Enzymes are biological catalysts that are typically composed of proteins, which accelerate chemical reactions by lowering the activation energy required. Enzymes have a specific active site that binds to their respective substrates, the reactants that they act upon. They catalyze reactions by holding substrates in an optimal orientation, destabilizing substrate bonds for easier breakage, providing favorable environmental conditions, or by forming transient covalent bonds. Significantly, enzymes are specific to substrates they bind, contradicting the idea that they are nonspecific.
Enzymes are not inorganic catalysts; rather, they are organic due to their proteinaceous nature. They do not increase, but instead decrease the amount of activation energy needed. Although primarily proteins, enzymes can also be made out of nucleic acids, specifically ribonucleic acid (RNA), in some cases. Furthermore, while enzymes might require minerals or vitamins as cofactors for their action, this does not change their fundamental requirement for a proper three-dimensional structure, determined by their amino acid sequence.