A substance that influences the reaction but does not participate in the reaction is

a catalyst

Explanation:

Catalyst is a substance that influences the rate of reaction without being consumed in the reaction. They increase the rate of reaction by decreasing the activation energy of the reaction. In biological system, enzymes are referred to as biological catalyst or biocatalyst. They are generally protein in nature and are very specific for their substrate. They also increases the rate of biological reaction by forming enzyme-substrate complex.

hope this helps and have a good day :-)

fossil's are like over rated rocks like low key not gonna lie i don't get why we can't just call them old rocks like for real i mean i call my grandpa and grandma that smh