Search results
Results from the WOW.Com Content Network
[4]: 188 The overall shape of the colony may be characterized as circular, irregular, or punctiform (like pinpoints). The vertical growth or elevation of the colony, another identifying characteristic, is assessed by tilting the agar plate to the side and is denoted as flat, raised, convex, pulvinate (very convex), umbilicate (having a ...
Colonies of Bacillus subtilis on a Petri dish can grow under controlled conditions. By varying agar concentration (which permits the control of the hardness of the medium), and the nutrient concentration, the response of the colony to external stresses can be studied. The different morphologies appear in the following growth conditions:
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).
Microscopic morphology differences can be used to differentiate them, since Arcanobacterium is rod-shaped and Streptococcus is coccus-shaped. [7] A. haemolyticum infection is most common in 15- to 25-year-old persons and manifests as exudative pharyngitis and/or tonsillitis accompanied by cervical lymphadenopathy. Symptoms look like those of β ...
The plates are incubated for 12 hours up to several days, depending on the test that is performed. Commonly used types of agar plates include: Red blood cells on an agar plate are used to diagnose infection. On the left is a positive Staphylococcus infection, on the right a positive Streptococcus culture.
The streak plate method is a way to physically separate the microbial population, and is done by spreading the inoculate back and forth with an inoculating loop over the solid agar plate. Upon incubation, colonies will arise and single cells will have been isolated from the biomass. Once a microorganism has been isolated in pure culture, it is ...
Colonies grown on rumen fluid-glucose-cellobiose agar (RGCA) complete medium for 5 days had a diameter of 0.5-1mm, were tan in color, and lenticular in shape. [9] Colonies grown in anaerobic conditions on blood agar plates were non-hemolytic and their morphology was white, shiny, circular, entire, convex, smooth, and translucent. [9]
Colony morphology of Flavobacteriia species Bergeyella zoohelcum on blood agar. Flavobacteriia are a type of gram-negative rod-shaped bacteria with sizes typically ranging from 0.1μm to 0.5μm wide and 2μm to 5μm long. [6] [22] Depending on the species of Flavobacteriia, the genome size can range from 1.85x10 9 daltons to 3.9x10 9 daltons. [23]