Tissue culture medium is sterilised by

Options

A. (a) Antifungal agents
B. (b) Keeping at `-20^(@)C`
C. (c) Autoclaving at `120^(@)C` for 15 minutes
D. (d) Filtering the medium

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the method used to sterilize the tissue culture medium. It's important to know that sterilization is crucial in tissue culture to prevent contamination.

2. **Identifying the Options**: The options provided are:
- A) Antifungal agents
- B) Keeping at minus 20 degrees Celsius
- C) Autoclaving at 120 degrees Celsius for 15 minutes
- D) Filtering the medium

3. **Analyzing Each Option**:
- **Option A (Antifungal agents)**: While antifungal agents can help prevent fungal growth, they do not sterilize the medium. They only inhibit growth but do not eliminate all microorganisms.
- **Option B (Keeping at minus 20 degrees Celsius)**: Freezing the medium at this temperature does not effectively sterilize it. It may slow down microbial growth but does not kill all microorganisms.
- **Option C (Autoclaving at 120 degrees Celsius for 15 minutes)**: This method involves using an autoclave, which is a device that uses steam under pressure to sterilize. At 120 degrees Celsius and 15 Pascal pressure, it effectively kills all microorganisms, making it a reliable method for sterilization.
- **Option D (Filtering the medium)**: Filtration can remove some microorganisms, but it is not effective for all, especially viruses. Therefore, it is not a complete sterilization method.

4. **Conclusion**: The most effective and reliable method for sterilizing tissue culture medium is **Option C: Autoclaving at 120 degrees Celsius for 15 minutes**.

**Final Answer**: Tissue culture medium is sterilized by autoclaving at 120 degrees Celsius for 15 minutes.

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