Final answer:
Most bacteria grow optimally at temperatures between 20°C and 45°C, with 37°C being optimal for human-associated bacteria. Excessive heat can cause protein denaturation and kill bacteria, affecting lab results and food safety.
Step-by-step explanation:
The typical temperature range at which most bacteria, specifically mesophiles, grow optimally is between 20°C to 45°C. These organisms thrive at moderate temperatures, which include the human body temperature of 37°C. It is important to avoid excessive heat when working with bacteria because temperatures exceeding their optimal range can lead to the rapid denaturation of proteins, essentially killing the bacteria and halting growth. This is important for ensuring the safety of food preparation and for maintaining the integrity of lab experiments.