Why is refrigeration considered a short-term method for storing bacteria in microbiology laboratories?

• A. Refrigeration kills all bacteria, making it unsuitable for long-term storage.
• B. Refrigeration causes bacteria to mutate rapidly, making them unusable for future experiments.
• C. Refrigeration slows bacterial metabolism but does not stop growth completely, so cultures eventually deteriorate.
• D. Refrigeration provides optimal conditions for bacterial reproduction, leading to overgrowth.

Answer: (C)

Verified step by step guidance

1. Understand that refrigeration is used to slow down bacterial metabolism and growth by lowering the temperature, which reduces enzymatic activity and cellular processes.
2. Recognize that refrigeration does not kill bacteria; instead, it merely slows their growth, meaning bacteria can still multiply, albeit at a much slower rate.
3. Consider that because bacteria continue to grow slowly, over time the culture can change in composition or deplete nutrients, leading to deterioration of the culture's quality.
4. Note that this slow growth and eventual deterioration make refrigeration suitable only for short-term storage, as the bacteria will not remain stable indefinitely.
5. Conclude that for long-term storage, methods that completely stop growth, such as freezing at very low temperatures or lyophilization (freeze-drying), are preferred.