At approximately 41°C, which group of bacteria is most likely to stop growing due to exceeding their optimal temperature range?

• A. Hyperthermophiles
• B. Mesophiles
• C. Thermophiles
• D. Psychrophiles

Answer: (B)

Verified step by step guidance

1. Understand the temperature ranges for each bacterial group: Psychrophiles thrive at cold temperatures (typically below 20°C), Mesophiles prefer moderate temperatures (around 20°C to 45°C), Thermophiles grow best at higher temperatures (around 45°C to 80°C), and Hyperthermophiles thrive at very high temperatures (above 80°C).
2. Identify the given temperature in the problem, which is approximately 41°C, and compare it to the optimal growth ranges of each bacterial group.
3. Recognize that 41°C is near the upper limit of the mesophiles' optimal temperature range, meaning temperatures above this can inhibit their growth.
4. Note that thermophiles and hyperthermophiles have optimal growth temperatures higher than 41°C, so they are unlikely to stop growing at this temperature.
5. Conclude that mesophiles are the group most likely to stop growing at approximately 41°C because this temperature exceeds their optimal range.