Answer:
Enzymes
Step-by-step explanation:
An example of a biological catalyst is an enzyme. A catalyst is a substance that quickens a chemical process. In order to cause a bond to form or break, an enzyme must first attach to its target, also known as a substrate. Although the enzyme does not really take part in the chemical reaction, it helps to make it happen and increases the likelihood that it will. Alcohol dehydrogenase is a prime illustration of this. This enzyme is in charge of cleansing your blood of alcohol. It functions by bringing the molecules of ethanol and NAD+ very close together and holding them there long enough for the ethanol molecule to transfer a hydrogen atom to NAD+, resulting in the formation of acetaldehyde and NADH. The byproducts of the conversion of acetaldehyde to acetyl CoA, which is utilized as energy, are expelled. There are several mechanisms by which enzymes can be controlled in the body, including pH and substrate concentration. You don't want an enzyme to be active if it isn't being used since it can start catalyzing things that you don't want it to. For instance, the stomach enzyme pepsin, which breaks down proteins, only works when the pH is below 4. (for reference, blood pH is 7.3 while stomach pH is around 2). This is extremely beneficial to your health since pepsin won't start working until it is secreted into the stomach, where it belongs. Your cells' proteins would be degraded if pepsin were present, which would be extremely harmful. Another method for controlling enzyme activity is substrate concentration. The rate of a reaction will decrease if you give an enzyme less substrate to work with (less substrate available for the enzyme).
Hope this makes sense!