Contents
How do you identify bacteria cells?
The organisms can be distinguished by the nature of their cell walls, by their shape, or by differences in their genetic makeup. The Gram stain is a test used to identify bacteria by the composition of their cell walls, named for Hans Christian Gram, who developed the technique in 1884.
What are the three main shapes of bacteria?
Individual bacteria can assume one of three basic shapes: spherical (coccus), rodlike (bacillus), or curved (vibrio, spirillum, or spirochete).
How are bacteria identified in the diagnostic laboratory?
The major impetus for bacterial identification came after the advent of solid culture media. Morphological appearance of bacterial colonies was often sufficient for their identification in the laboratory. Even in modern times, preliminary identification of most cultivable bacteria is based on such morphological characters.
How can you tell what type of bacteria you have?
Observe the shape of the bacteria. Once you have used staining to determine whether your bacteria are Gram positive, Gram negative, or acid-fast, it’s time to narrow down the type of bacteria. The first step is to observe the shape (s) of the bacteria on the slide. The 3 most common shapes are coccus (spherical), bacillus (rod-shaped), and spiral.
What are the steps in the identification of unknown bacteria?
Various steps involved in the identification of unknown bacteria are: Isolation: The importance of this step is to isolate pure colonies of bacteria. The streak plate is a qualitative isolation method; quadrant streaking is mostly done to obtain pure colonies.
How is the shape of a bacterial colony determined?
2. Based on the shape. The structure of bacteria varies like spherical (cocus), bar or stick like (bacilli), chain-like (strepto), comma-shaped like virbrio-cholera bacteria. Even the shape of the bacteria colony grown on the nutrition medium also differ for a different strain of bacteria.