Here's why:

* Enzyme function is determined by the enzyme's shape and chemical properties. The color of an enzyme is a result of its chemical structure, but it doesn't directly impact its ability to catalyze a reaction.

* Factors that DO affect enzyme function include:

* Temperature: Enzymes have an optimal temperature range. Outside this range, their activity decreases.

* pH: Each enzyme has an optimal pH. Extreme pH values can denature the enzyme, altering its shape and rendering it inactive.

* Substrate concentration: The rate of reaction increases as substrate concentration increases, until the enzyme becomes saturated.

* Presence of inhibitors: Inhibitors can bind to enzymes and interfere with their activity.

* Presence of activators: Activators can bind to enzymes and increase their activity.

Let me know if you have any other questions!