Enzymes are proteins that act as catalysts in biological reactions. Here's a breakdown:

* Proteins: Enzymes are made up of long chains of amino acids, folded into specific three-dimensional structures. This structure is crucial for their function.

* Catalysts: Enzymes speed up chemical reactions without being consumed in the process. They do this by lowering the activation energy needed for the reaction to occur.

Key points to remember about enzymes:

* Specificity: Each enzyme typically catalyzes only one or a small number of reactions, making them highly specific.

* Active site: Enzymes have a region called the active site where the substrate (the molecule being acted upon) binds and the reaction occurs.

* Regulation: Enzyme activity can be regulated by factors like temperature, pH, and the presence of inhibitors or activators.

Let me know if you have any other questions about enzymes!