Search results
Results From The WOW.Com Content Network
Colony-forming units are used to quantify results in many microbiological plating and counting methods, including: The pour plate method wherein the sample is suspended in a Petri dish using molten agar cooled to approximately 40–45 °C (just above the point of solidification to minimize heat-induced cell death).
By the counting of cells in a known small volume, the concentration can be mediated. Examples of the need for cell counting include: In medicine, the concentration of various blood cells, such as red blood cells and white blood cells, can give crucial information regarding the health situation of a person (see: complete blood count).
Plaques from a virus isolated from a compost heap near UCLA. The bacterium is M. smegmatis.. A viral plaque is a visible structure formed after introducing a viral sample to a cell culture grown on some nutrient medium.
Graphic depicting the human skin microbiota, with relative prevalences of various classes of bacteria. The human microbiome is the aggregate of all microbiota that reside on or within human tissues and biofluids along with the corresponding anatomical sites in which they reside, [1] [2] including the gastrointestinal tract, skin, mammary glands, seminal fluid, uterus, ovarian follicles, lung ...
The cell wall of some Gram-positive bacteria can be completely dissolved by lysozymes which attack the bonds between N-acetylmuramic acid and N-acetylglucosamine. In other Gram-positive bacteria, such as Staphylococcus aureus, the walls are resistant to the action of lysozymes. [4] They have O-acetyl groups on carbon-6 of some muramic acid ...
The great plate count anomaly. Counts of cells obtained via cultivation are orders of magnitude lower than those directly observed under the microscope. This is because microbiologists are able to cultivate only a minority of naturally occurring microbes using current laboratory techniques, depending on the environment.
The pour plate technique is the typical technique used to prepare plate count agars. Here, the inoculum is added to the molten agar before pouring the plate. The molten agar is cooled to about 45 degrees Celsius and is poured using a sterile method into a petri dish containing a specific diluted sample.
Spiral plating is used extensively for microbiological testing of food, milk and milk products and cosmetics. It is an approved method by the FDA. [2] The advantage of spiral plating is less plates used versus plating manually because different concentrations are present on each plate.