Spread plate technique applies the sample by:

Spread plate technique applies the sample by:

• A. A small amount of a previously diluted specimen is spread over the surface of a solid medium using a spreading rod
• B. A loop is used to streak the surface
• C. A drop is placed on agar
• D. A swab is dabbed on surface

Answer: (A)

In spread plate technique, the goal is to distribute a diluted microbial sample evenly across the surface of an agar plate so individual cells form isolated colonies that can be counted. This is done by taking a small volume of a diluted sample and spreading it with a sterile spreading rod (a glass hockey-stick) over the entire surface, creating a thin, even film. The dilution step is crucial because it helps ensure that colonies are well separated rather than growing into a dense blob. This approach differs from other methods. Using a loop to streak the surface is a streak plate technique, which aims to dilute the sample progressively by streaking across sections to obtain isolated colonies but not by spreading a uniform film. Dropping a small amount of liquid on the agar is often used for drop or spot plating, which concentrates cells in a specific area rather than spreading evenly for counting. Dabbling a swab on the surface is a swab inoculation method used for sampling or transferring material, not for producing an even spread for colony counting.

In spread plate technique, the goal is to distribute a diluted microbial sample evenly across the surface of an agar plate so individual cells form isolated colonies that can be counted. This is done by taking a small volume of a diluted sample and spreading it with a sterile spreading rod (a glass hockey-stick) over the entire surface, creating a thin, even film. The dilution step is crucial because it helps ensure that colonies are well separated rather than growing into a dense blob.

This approach differs from other methods. Using a loop to streak the surface is a streak plate technique, which aims to dilute the sample progressively by streaking across sections to obtain isolated colonies but not by spreading a uniform film. Dropping a small amount of liquid on the agar is often used for drop or spot plating, which concentrates cells in a specific area rather than spreading evenly for counting. Dabbling a swab on the surface is a swab inoculation method used for sampling or transferring material, not for producing an even spread for colony counting.