Which bacterial culture will have the highest growth rate?

• A. E. coli bacteria being grown between the temperatures of 37°C & 40°C (optimal temperatures).
• B. E. coli bacteria being grown between the temperatures of 15°C & 20°C (minimum temperatures).
• C. E. coli bacteria being grown at 45°C (maximum temperature).
• D. E. coli bacteria would grow at the same rate at any temperature.

Answer: (A)

Verified step by step guidance

1. Identify the optimal growth temperature range for E. coli, which is typically between 37°C and 40°C. This is where the bacteria's enzymes function most efficiently, leading to the highest growth rate.
2. Understand that at temperatures below the optimal range, such as 15°C to 20°C, the metabolic activities of E. coli slow down, resulting in a reduced growth rate.
3. Recognize that at temperatures above the optimal range, such as 45°C, the proteins and enzymes in E. coli may begin to denature, which can inhibit growth or even kill the bacteria.
4. Consider the concept of cardinal temperatures for bacterial growth: minimum, optimum, and maximum. E. coli has a specific range for each, with the optimum being the most conducive to rapid growth.
5. Conclude that E. coli will have the highest growth rate at its optimal temperature range of 37°C to 40°C, as this is where the conditions are most favorable for its cellular processes.