Changing environmental conditions like temperature or pH can alter an enzyme's shape, particularly affecting the active site where substrate binding occurs. This change in shape can significantly affect the enzyme’s function in the following ways:

• High temperatures can break the bonds holding the enzyme's structure together, causing the enzyme to lose its specific shape in a process called denaturation. When denatured, the active site no longer fits the substrate, and enzyme activity stops. This denaturation is usually irreversible.

• Low temperatures do not denature enzymes but slow their function by reducing kinetic energy and the frequency of successful collisions between enzyme and substrate.

• pH changes alter charged amino acids in the enzyme, disrupting intramolecular interactions and changing the enzyme’s shape and active site. Each enzyme has an optimum pH, and deviations from this can reduce or stop enzyme activity. Extreme pH values may also denature enzymes, often irreversibly.

In summary, altered environmental conditions that affect enzyme shape will typically reduce or halt enzyme function by preventing substrate binding or catalysis due to changes in the active site's structure.