* Enzymes are biological catalysts. This means they speed up chemical reactions without being consumed in the process.

* Enzymes are highly specific. Each enzyme typically catalyzes only one or a very small number of reactions. This specificity is due to the unique shape of the enzyme's active site.

* Enzymes lower the activation energy of reactions. Activation energy is the minimum energy required for a reaction to occur. Enzymes provide an alternative reaction pathway with a lower activation energy, allowing the reaction to proceed more quickly.

* Enzymes are proteins (mostly). While the vast majority of enzymes are proteins, there are a few exceptions. Some RNA molecules, known as ribozymes, also have catalytic activity.

* Enzymes are affected by temperature and pH. Enzymes have an optimal temperature and pH range at which they function best. Outside of this range, enzyme activity can decrease or even stop.

* Enzymes can be regulated. Cells can control the activity of their enzymes through various mechanisms, including:

* Competitive inhibition: A molecule binds to the active site of an enzyme, preventing the substrate from binding.

* Non-competitive inhibition: A molecule binds to the enzyme at a site other than the active site, changing the enzyme's shape and reducing its activity.

* Allosteric regulation: A molecule binds to an enzyme at a regulatory site, causing a conformational change that either increases or decreases activity.

Let me know if you'd like more details on any of these points!