What happens to enzymes when the temperature is too high?

When temperatures exceed the optimal range for enzyme activity, the enzymes undergo a process called denaturation. This means that the increased thermal energy disrupts the bonds that maintain the enzyme's three-dimensional structure. As a result, the shape of the enzyme changes, particularly at the active site where substrates bind. This alteration in shape renders the enzyme ineffective in catalyzing reactions since the substrate can no longer fit properly.

Denaturation is often reversible but can be irreversible if the conditions are extreme enough or prolonged. Hence, while enzymes may become inactive at elevated temperatures, they are typically denatured and lose their original functional shape instead of just turning inactive or becoming permanently inactive without the structural changes. This is why understanding the relationship between temperature and enzyme structure is crucial in biology, as it highlights how environmental factors influence biochemical reactions.