How does an autoclave kill microorganisms?

• A. By lowering the pH to create an acidic environment
• B. By using pressurized steam to denature proteins and destroy cellular structures
• C. By exposing microorganisms to ultraviolet radiation
• D. By dehydrating cells through dry heat

Answer: (B)

Verified step by step guidance

1. Understand that an autoclave is a device used to sterilize equipment and materials by killing microorganisms.
2. Recognize that the autoclave uses pressurized steam, which increases the temperature above the normal boiling point of water, typically around 121°C under pressure.
3. Know that the high temperature and pressure cause proteins in microorganisms to denature, meaning their structure is altered so they lose function.
4. Realize that this denaturation, along with the destruction of cellular structures such as membranes and enzymes, leads to the death of the microorganisms.
5. Contrast this method with other sterilization techniques like UV radiation or dry heat, which work differently and are not the primary mechanism in an autoclave.