Liquid nitrogen

Definition

Liquid nitrogen is nitrogen in a liquid state at an extremely low temperature, commonly used for rapid freezing and cryopreservation.

5 Must Know Facts For Your Next Test

1. Liquid nitrogen boils at -196°C (-320°F) which makes it effective for rapid cooling.
2. It is used to control microbial growth by freezing microorganisms, making them inactive.
3. Cryopreservation with liquid nitrogen allows long-term storage of biological samples like microbes.
4. Safety precautions are crucial when handling liquid nitrogen because of its extreme cold and potential to cause severe frostbite or asphyxiation.
5. In microbiology labs, liquid nitrogen is often used in conjunction with other methods to ensure microbial cultures remain viable over extended periods.

Review Questions

• At what temperature does liquid nitrogen boil?
• How does liquid nitrogen contribute to the control of microbial growth?
• What safety measures should be taken when handling liquid nitrogen?

Related terms

Cryopreservation:

The process of preserving cells, tissues, or organisms by cooling them to sub-zero temperatures.

Freezing Point: The temperature at which a liquid turns into a solid.

Microbial Viability: The ability of microorganisms to survive and maintain their potential for growth.