GLOSSARY

Enzymes is a biological catalyst accelerating a defined reaction.

An enzyme accelerates a reaction by lowering its activation barrier, without changing the final equilibrium or reaction free-energy difference. It is not consumed overall during a catalytic cycle, although it can be degraded or inactivated. Most enzymes are proteins, but catalytic RNA also exists. More enzyme increases reaction rate only when other constraints allow it; substrate supply, products and conditions still matter.

Specificity may concern substrate identity, reaction type or molecular stereochemistry; these are related but distinct properties. Some enzymes accept several related substrates while others have a narrower range. A family name alone cannot establish every member's exact function. Nutritionally, a similar molecule or possible binding does not prove effective processing through the intended pathway; correct substrate, reaction and conditions must be considered together.

Binding, conformational adjustment, chemistry and product release are connected steps of an enzyme cycle, and each step's rate can matter. Lock-and-key is a useful simplified teaching model but incompletely represents protein flexibility; induced fit and selection among existing conformations give a more dynamic view. Tighter binding does not always produce faster turnover or more product, because chemical conversion and release must also occur.

For example, after training changes an enzyme result, first ask whether it was measured in blood, tissue or purified protein. Then assess assay conditions, nutrition and time since the last session alongside actual performance; this comparison helps distinguish a regulatory response from a nutritional deficiency or a presumed supplement need.