Final answer:
True, enzyme-substrate affinity is influenced by pH and temperature. Environmental conditions outside the optimal ranges can denature enzymes and impair their ability to bind to substrates, affecting their catalytic activity.
Step-by-step explanation:
The statement that enzyme-substrate affinity can be affected by pH or temperature is true. Enzymes, which are specialized proteins, are optimized to work under specific environmental conditions, including optimal ranges of temperature and pH. Variations outside of these ranges can lead to changes in the shape of the enzyme's active site, affecting its ability to bind to the substrate. High temperatures can cause enzymes to denature, losing their functional shape. Similarly, extreme pH levels can also denature enzymes, disrupting their function. Therefore, both factors are crucial in influencing the efficiency and activity of enzymes.