Table of Contents
Which ingredient in PEA supplies Carbon? Casein (milk protein) and soybean meal provide carbon, largely in the form of the protein. What ingredient in PEA supplies Nitrogen? Because they contain protein, casein, and soybean act as nitrogen sources.
What ingredients are in EMB agar Supply Carbon?
What ingredient in EMB agar supplies Carbon? The sugars, lactose and sucrose.
What ingredients are in Columbia CNA supplies carbon?
Which ingredient(s) in Columbia CNA plus 5% sheep blood agar supply(ies): Carbon? Nitrogen? 1) Casein (mild protein), animal tissue, yeast extract, beef extract, and corn starch can all supply carbon in a variety of forms.
Is Pea a defined or undefined medium provide the reasoning behind your choice and explain why this formulation is desirable?
Is PEA a defined or an undefined medium? Provide the reasoning behind your choice and explain why this formulation is desirable. i. It is an undefined medium that contains more preformed nutrients/growth factors, so it better supports bacterial growth.
What type of medium is MacConkey agar?
MacConkey agar is an example of a medium that is both differential and selective. The presence of bile salts, as well as crystal violet, within the media prevent gram-positive organisms from growing.
Is EMB defined or undefined?
Eosin methylene blue agar (EMB) is an undefined medium. EMB is a complex medium consisting of peptone, dipotassium phosphate, lactose, eosin Y (dye),.
What is the carbon source in EMB?
Peptic digest of animal tissue serves as source of carbon, nitrogen, and other essential growth nutrients. Lactose serves as the source of energy by being the fermentable carbohydrate. Eosin-Y and methylene blue serve as differential indicators.
What ingredients in peas supply nitrogen?
What ingredient in PEA supplies Nitrogen? Because they contain protein, casein, and soybean act as nitrogen sources.
What ingredients are in MSA supplies nitrogen?
Enzymatic digest of casein, enzymatic digest of animal tissue, and beef extract provide the nitrogen, vitamins, and carbon in Mannitol Salt Agar. D-Mannitol is the carbohydrate source.
Which ingredient S in MSA supply ies a carbon?
(a) Carbon: Proteose peptone, beef extract, and d-mannitol.
What do deamination and decarboxylation have in common?
What do deamination and decarboxylation reactions have in common? They are both enzymes that catalyze the removal of amino acids groups. Purple= positive test that produces decarboxylation, organism produces the speific decarboxylation enzyme.
What media contain at least one ingredient that is not chemically definable?
Answer: Synthetic media contain pure organic and inorganic compounds that are chemically defined (i.e. known molecular formula). Complex or enriched media contain ingredients that are not chemically defined or pure (i.e. animal extracts). Enriched media are used to grow fastidious bacteria.
What purpose does the nutrient agar plate serve MacConkey?
What is the purpose of the nutrient agar plate? It shows normal growth and appearance of the bacteria when grown on agar. It serves as a control for comparison to growth on MacConkey agar.
What ingredients make MacConkey agar differential?
This medium is both selective and differential. The selective ingredients are the bile salts and the dye, crystal violet which inhibit the growth of Gram-positive bacteria. The differential ingredient is lactose.
What is the composition of MacConkey agar?
MacConkey agar contains four key ingredients (lactose, bile salts, crystal violet, and neutral red) that make it a selective and differential media. Bile salts and crystal violet act as selective agents that inhibit the growth of Gram-positive organisms, and proliferate the selective growth of gram-negative bacteria.
What is blood agar made of?
Blood agar is a general purpose, enriched medium often used to grow fastidious organisms and to differentiate bacteria based on their hemolytic properties. In the U.S., blood agar is usually prepared from tryptic soy agar or Columbia agar base with 5% sheep blood.
Is agar defined or undefined?
Like other growth media, the formulations of agar used in plates may be classified as either “defined” or “undefined”; a defined medium is synthesized from individual chemicals required by the organism so the exact molecular composition is known, whereas an undefined medium is made from natural products such as yeast.
Would removing bile salts and or crystal violet from MacConkey?
How would removing crystal violet from MacConkey Agar alter the sensitivity and specificity of the medium? It would inhibit the growth of gram positive bacteria because this test is used to differentiate the gram positive bacteria and enterobacteria. What color is Gram +?.
Is mannitol salt agar defined or undefined?
Is MSA a defined or undefined medium? MSA is an undefined medium because the exact composition of beef extract and peptone are unknown. The goal of this medium is to isolate desired organisms, and once the undesired organisms have been inhibited, you want the desired ones to grow well.
What is EMB agar differential for?
Eosin methylene blue agar (EMB) is a selective and differential medium used to isolate fecal coliforms. Eosin Y and methylene blue are pH indicator dyes which combine to form a dark purple precipitate at low pH; they also serve to inhibit the growth of most Gram positive organisms.
What is EMB agar used for?
EMB agar is used in water quality tests to distinguish coliforms and fecal coliforms that signal possible pathogenic microorganism contamination in water samples.
What bacteria grows on EMB?
Some gram-positive bacteria, such as enterococci, staphylococci, and yeast will grow on this medium and usually form pinpoint colonies. Non-pathogenic, non-lactose-fermenting organisms will also grow on this medium.
What bacteria grows on MSA?
Result Interpretation on Mannitol Salt Agar Organisms Results Staphylococcus aureus Yellow colonies with yellow zones. Staphylococci other than S. aureus (e.g. Staphylococcus epidermidis ) Colorless or Red colonies with red zones. Streptococci No growth to trace growth. Micrococci Large white to orange.
What does MSA differentiate between?
Mannitol Salt Agar (MSA) is a selective and differential medium. The high concentration of salt (7.5%) selects for members of the genus Staphylococcus, since they can tolerate high saline levels. Organisms from other genera may grow, but they typically grow very weakly.
Is MSA selective or differential?
This type of medium is both selective and differential. The MSA will select for organisms such as Staphylococcus species which can live in areas of high salt concentration (plate on the left in the picture below).
