Use the following graph to answer questions 3 and 4.
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Which of the lines best depicts the log phase of a thermophile incubated at room temperature?

Verified step by step guidance

1. Identify the characteristics of the log phase in bacterial growth, which is characterized by exponential growth where the number of cells doubles at a constant rate.
2. Understand that thermophiles are microorganisms that thrive at relatively high temperatures, typically between 41°C and 122°C.
3. Consider that room temperature is approximately 20°C to 25°C, which is significantly lower than the optimal growth temperature for thermophiles.
4. Recognize that at room temperature, a thermophile would not be in its optimal growth environment, likely resulting in a slower growth rate or no growth at all.
5. Examine the graph to identify the line that shows little to no increase in cell number, as this would best depict the log phase of a thermophile incubated at room temperature.

Key Concepts

Log Phase of Bacterial Growth

The log phase, or exponential phase, is a period in bacterial growth where cells divide at a constant and rapid rate, leading to a significant increase in population. During this phase, the conditions are optimal for growth, and the rate of cell division is determined by factors such as nutrient availability and environmental conditions. Understanding this phase is crucial for interpreting growth curves and predicting microbial behavior.

Thermophiles

Thermophiles are microorganisms that thrive at relatively high temperatures, typically between 45°C and 80°C. They possess specialized enzymes and cellular structures that allow them to maintain stability and function in extreme heat. When studying thermophiles at room temperature, it is important to recognize how their growth patterns may differ from mesophilic organisms, particularly in terms of their metabolic rates and growth phases.

Growth Curve Interpretation

A growth curve is a graphical representation of the growth of a microbial population over time, typically divided into four phases: lag, log, stationary, and death. Each phase reflects different physiological states of the population, influenced by factors like nutrient availability and waste accumulation. Accurately interpreting these curves is essential for understanding microbial dynamics and can help identify the log phase in the context of the question regarding thermophiles.