Bacterial lawn

Definition

A bacterial lawn is a uniform and continuous layer of bacteria grown on an agar plate. This technique is often used to study the effects of bacteriophages and antibiotics.

5 Must Know Facts For Your Next Test

1. A bacterial lawn is created by spreading a high concentration of bacterial cells evenly across an agar surface.
2. It helps in the isolation and identification of viruses, especially bacteriophages that create clear zones known as plaques.
3. The uniform growth allows for easy observation of virus-induced lysis or antibiotic effectiveness.
4. Bacterial lawns are commonly used in plaque assays to quantify viral particles
5. The method usually involves using a soft agar overlay to facilitate even distribution and growth.

Review Questions

• What is the primary purpose of creating a bacterial lawn on an agar plate?
• How can you identify the presence of bacteriophages on a bacterial lawn?
• Why is it important for the bacterial cell concentration to be high when creating a bacterial lawn?

Related terms

Plaque Assay: A method used to count and measure the concentration of viral particles by observing clear zones in a bacterial lawn.

Bacteriophage: A virus that infects and replicates within bacteria, often forming plaques on bacterial lawns.

Soft Agar Overlay: A technique involving a semi-solid layer used over an initial agar plate to facilitate even distribution and growth of bacteria or viruses.