microbiology lab
Abstract
The primary focus of this lab was on microscopy and simple stains. Crystal violet and Carbol fuchsine, simple staining components, were used to stain the slide in order to see the different microbes in order to determine their cellular shape and identify unknown ones by comparing.
Introduction
Bacterial cells are usually colorless because cytoplasm, for the most part, is transparent. Since the bacteria are colorless, it is almost essential to add a stain to make the bacteria more visible. Once stained, cell morphology can be observed.
Stains are solutions that contain a solute called a chromophore dissolved in a solvent. A chromophore is the color possessing portion of the solution and is therefore responsible for the stains color. The ability of a stain to bind to macromolecular cellular components such as protein or nucleic acids depends on the electrical charge found on the chromogen portion, as well as on the cellular component to be stained. There are 2 types of stain:
Acidic stains – a chromogen portion exhibits a negative charge, therefore has a strong affinity for the positive constituents of the cell
Basic stains – a chromogen portion exhibits a positive charge, therefore has a strong affinity for the negative constituents of the cell
Bacterial cells usually have a negative surface charge, meaning that a positively charged stain is needed to stain the surface of the cell. When the stain is applied, there is an attraction between the negatively charged cell surface and the positively charged chromophore, leading to the surface of the cell taking on the color of the stain.
Numerous staining techniques are available for visualization, differentiation and separation of bacteria in terms of morphological characteristics and cellular structures.
Simple staining used for visualization of morphological shape and arrangement
Differential staining used for:
1) Separation into groups (Gram stain & Acid-fast stain)
2)
The primary focus of this lab was on microscopy and simple stains. Crystal violet and Carbol fuchsine, simple staining components, were used to stain the slide in order to see the different microbes in order to determine their cellular shape and identify unknown ones by comparing.
Introduction
Bacterial cells are usually colorless because cytoplasm, for the most part, is transparent. Since the bacteria are colorless, it is almost essential to add a stain to make the bacteria more visible. Once stained, cell morphology can be observed.
Stains are solutions that contain a solute called a chromophore dissolved in a solvent. A chromophore is the color possessing portion of the solution and is therefore responsible for the stains color. The ability of a stain to bind to macromolecular cellular components such as protein or nucleic acids depends on the electrical charge found on the chromogen portion, as well as on the cellular component to be stained. There are 2 types of stain:
Acidic stains – a chromogen portion exhibits a negative charge, therefore has a strong affinity for the positive constituents of the cell
Basic stains – a chromogen portion exhibits a positive charge, therefore has a strong affinity for the negative constituents of the cell
Bacterial cells usually have a negative surface charge, meaning that a positively charged stain is needed to stain the surface of the cell. When the stain is applied, there is an attraction between the negatively charged cell surface and the positively charged chromophore, leading to the surface of the cell taking on the color of the stain.
Numerous staining techniques are available for visualization, differentiation and separation of bacteria in terms of morphological characteristics and cellular structures.
Simple staining used for visualization of morphological shape and arrangement
Differential staining used for:
1) Separation into groups (Gram stain & Acid-fast stain)
2)