Which one of the following temperatures would most likely kill a mesophile?
a. -50℃
b. 0℃
c. 9℃
d. 37℃
e. 60℃

Verified step by step guidance

1. Understand the definition of a mesophile: Mesophiles are microorganisms that thrive at moderate temperatures, typically between 20℃ and 45℃.
2. Identify the temperature range that is lethal for mesophiles: Temperatures significantly above or below their optimal range can be lethal.
3. Analyze each option: a. -50℃ is far below the optimal range and would likely freeze and kill the mesophile. b. 0℃ is below the optimal range and could inhibit growth but not necessarily kill. c. 9℃ is below the optimal range but not lethal. d. 37℃ is within the optimal range for mesophiles. e. 60℃ is above the optimal range and could denature proteins, leading to death.
4. Determine which temperature is most likely to kill a mesophile: Consider which temperature is most extreme relative to the mesophile's optimal range.
5. Conclude that the temperature most likely to kill a mesophile is the one that is significantly higher than their optimal range, as high temperatures can denature proteins and disrupt cellular processes.

Key Concepts

Mesophiles

Mesophiles are microorganisms that thrive at moderate temperatures, typically between 20°C and 45°C. They are commonly found in environments such as soil and the human body, where temperatures are conducive to their growth. Understanding the temperature range for mesophiles is crucial for determining conditions that can inhibit or kill these organisms.

Thermal Death Point

The thermal death point is the lowest temperature at which a specific microorganism is killed within a defined period. For mesophiles, temperatures above their optimal growth range can lead to cell damage and death. Knowing the thermal death point helps in food preservation and sterilization processes.

Temperature Effects on Microbial Growth

Temperature significantly affects microbial growth, influencing enzyme activity, membrane fluidity, and overall metabolism. Each microorganism has a specific temperature range for growth, including minimum, optimum, and maximum temperatures. Recognizing these effects is essential for predicting microbial behavior under varying thermal conditions.