1. Temperature: Enzymes have an optimal temperature range where they function best.

* Increasing temperature generally increases enzyme activity up to a point, as molecules move faster and collide more frequently.

* Beyond the optimal temperature, the enzyme begins to denature (lose its shape), leading to a decrease in activity.

* Very high temperatures can completely inactivate the enzyme.

2. pH: Enzymes also have an optimal pH range.

* Changes in pH can disrupt the ionic bonds and other interactions that hold the enzyme in its active conformation.

* Extreme pH values can denature the enzyme and cause it to lose its activity.

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