On which of the following plates do you predict Escherichia coli would grow the most slowly?

• A. Nutrient agar plate
• B. Minimal agar plate lacking a carbon source
• C. Luria-Bertani (LB) agar plate
• D. Tryptic soy agar plate

Answer: (B)

Verified step by step guidance

1. Step 1: Understand the growth requirements of Escherichia coli (E. coli). E. coli is a facultative anaerobic bacterium that requires essential nutrients such as carbon, nitrogen, vitamins, and minerals to grow and multiply.
2. Step 2: Analyze the composition of each agar plate. Nutrient agar, LB agar, and Tryptic soy agar are all rich media containing a variety of nutrients including carbon sources, which support robust bacterial growth.
3. Step 3: Consider the minimal agar plate lacking a carbon source. Since carbon is a fundamental element for building cellular components and generating energy, its absence severely limits bacterial growth.
4. Step 4: Predict growth rates based on nutrient availability. E. coli will grow fastest on nutrient-rich media (Nutrient agar, LB agar, Tryptic soy agar) and slowest or not at all on minimal agar lacking a carbon source due to nutrient limitation.
5. Step 5: Conclude that the minimal agar plate lacking a carbon source will result in the slowest growth of E. coli because it cannot synthesize essential biomolecules or generate energy efficiently without carbon.