- 1 What is the application purpose of Columbia CNA with 5 sheep blood agar?
- 2 What is the application of Columbia CNA?
- 3 Is Columbia CNA agar a defined or an undefined medium provide the reasoning behind your choice and explain why this formulation is desirable?
- 4 What is the application of using the CNA blood plate?
- 5 What bacteria does not grow on blood agar?
- 6 Is blood agar selective or differential?
- 7 Why is CNA differential?
- 8 What makes CNA differential?
- 9 Why is Columbia CNA agar selective?
- 10 What is the application of MacConkey agar?
- 11 What did you use to establish what constituted good growth?
- 12 Why is it necessary to use two controls rather than just one what are the specific purposes of each?
- 13 Is Mac selective or differential?
- 14 Which type of organisms will grow on CNA sheep blood media?
- 15 What is b hemolysis?
What is the application purpose of Columbia CNA with 5 sheep blood agar?
Columbia agar with sheep blood supplemented with the CNA inhibitory mixture (Colistin + Nalidixic Acid) is a selective medium for Gram (+) bacteria. It is also used to demonstrate haemolytic reactions. This medium is used for the analysis of mixed flora specimens, such as genital tract or oropharyngeal specimens.
What is the application of Columbia CNA?
Columbia CNA Agar has traditionally been used to identify staphylococci and streptococci. The addition of sheep blood to the medium allows distinct identification of S. pneumoniae through the production of clear alpha-haemolysis.
Is Columbia CNA agar a defined or an undefined medium provide the reasoning behind your choice and explain why this formulation is desirable?
Columbia CNA agar is selective and differential medium. Is Columbia CNA agar defined or undefined medium. Provide the reasoning behind your choice and explain why this formulation is desirable. It is undefined due to the casein, animal tissue, yeast extract, beef extract, and corn starch in the medium.
What is the application of using the CNA blood plate?
A CNA-blood plate is both selective and differential. It selects for Gram(+), coccus-shaped bacteria and selects against everything else. CNA-blood is also differential. It will differentiate between Gram(+) cocci based on their ability to hemolyze blood, just like a TSA-blood plate (alpha, beta or gamma).
What bacteria does not grow on blood agar?
Fastidious organisms, such as streptococci, do not grow well on ordinary growth media but grow on blood agar.
Is blood agar selective or differential?
Blood agar is differential media because 3 different types of hemolysis, or lysing of red blood cells, can be seen on this plate.
Why is CNA differential?
This medium is basically blood agar, containing 5% sheep’s blood mixed with either TSA base or Columbia agar base. The differentiation of blood agar is due to the ability of many bacteria to hemolyze blood cells, using chemicals called hemolysins..
What makes CNA differential?
CNA-blood agar contains the selective agents colisten and nalidixic acid. The CNA-blood agar, like the TSA-blood agar is differential. The differential material in both is defibrinated red blood cells. Bacteria that can metabolize whole RBC’s do so by producing the enzyme hemolysin.
Why is Columbia CNA agar selective?
Columbia-CNA Agar. Columbia-CNA Agar (C-CNA) is a type of selective media which selects for Gram-positive bacteria. It contains two antibiotics, colistin and naladixic acid, which inhibit the growth of gram-negative bacteria, thus selecting for Gram-positive organisms.
What is the application of MacConkey agar?
MacConkey agar is used for the isolation of gram-negative enteric bacteria. It is used in the differentiation of lactose fermenting from lactose non-fermenting gram-negative bacteria. It is used for the isolation of coliforms and intestinal pathogens in water, dairy products and biological specimens.
What did you use to establish what constituted good growth?
What did you use to establish what constituted “good growth?” The nutrient agar plate inoculated with the same organisms provided examples of what “good growth” for each organism looks like on a nonselective media.
Why is it necessary to use two controls rather than just one what are the specific purposes of each?
It is important to use 2 controls because the tubes show “no color change” under 2 different conditions (anaerobic and aerobic). All enterics are facultative anaerobes; they have both respiratory and fermentative enzymes. What color results would you expect for organisms of O-F glucose media inoculated with an enteric?
Is Mac selective or differential?
MacConkey agar is a selective and differentiating agar that only grows gram-negative bacterial species; it can further differentiate the gram-negative organisms based on their lactose metabolism.
Which type of organisms will grow on CNA sheep blood media?
BD Columbia CNA Agar with 5% Sheep Blood is a selective medium used for the isolation of gram-positive bacteria (especially staphylococci and streptococci) from clinical specimens.
What is b hemolysis?
Beta hemolysis (β) is defined as complete or true lysis of red blood cells.