Unit 7 Quizzes Flashcards
If the photo below is of bacteria growing on TSA-blood agar medium, can you determine if the bacteria is Gram(+) or Gram(-)?
A) Yes, because TSA-blood medium is selective as well as differential.
B) No, because TSA-blood is only a differential, not selective medium.
B) No, because TSA-blood is only a differential, not selective medium.
What type of blood hemolysis do you see on this CNA-blood agar medium?
A) beta or complete hemolysis
B) alpha or partial hemolysis
C) gamma, no hemolysis
B) alpha or partial hemolysis
What is the supportive ingredient in Chocolate Agar?
lysed sheep red blood cells
CNA blood agar differentiates according to bacterial
A) blood hemolysis
B) cell wall type
C) lactose fermentation
D) glucose fermentation
A) blood hemolysis
Blood hemolyisis is associated with pathogenicity because:
A) Bacteria that can hemolyse blood can evade phagocytosis.
B) Blood hemolysis allows bacteria to live in the nose, throat and intestines.
C) Bacteria that can hemolize blood can utilize the nutrients in the blood to grow.
D) Blood hemolysis provides DNA for bacterial growth.
C) Bacteria that can hemolize blood can utilize the nutrients in the blood to grow.
What does a clear growth (not pink) of bacteria signify on MacConkey medium?
A) The organism has the enzyme lactase
B) The organism is a coliform
C) The organism is a non-coliform
D) The organism is not a pathogen
C) The organism is a non-coliform
What does bacterial growth with olive green color in the agar around the growth signify on TSA-Blood media?
A) Alpha hemolysis
B) Gamma hemolysis
C) Beta hemolysis
A) Alpha hemolysis
All of the following provide nutrition in basic media EXCEPT:
A) digested yeast
B) digested soy
C) digested milk
D) agar
D) agar
An organism growing on MacConkey medium with no color change in the medium (a clear growth pattern) is which of the following? Choose all that apply.
A) Lacks the enzyme lactase
B) Has the enzyme lactase
C) Coliform
D) Gram positive
E) Gram negative
F) Is likely a pathogen
G) Cannot ferment lactose
H) Can ferment lactose
I) Not likely pathogenic
J) Non-coliform
A) Lacks the enzyme lactase
E) Gram negative
F) Is likely a pathogen
G) Cannot ferment lactose
J) Non-coliform
The bacteria that lives in the intestines and ferments lactose is:
A) Proteus vulgaris
B) Staphylococcus aureus
C) Priestia megaterium
D) E. coli
D) E. coli
TSA-blood is:
A) differential
B) supportive
C) non differential
D) both supportive and differential
A) differential
Blood is a source of all of the following EXCEPT:
A) amino acids
B) growth factors NAD and hemin
C) DNA
D) iron
C) DNA
This bacteria growing on MacConkey ferments _______.
Lactose
What is the differential ingredient in CNA blood?
A) lactose
B) whole sheep red blood cells
C) CNA
D) crystal violet and bile salts
B) whole sheep red blood cells
An organism growing on TSA Blood that produces NO change in the red blood cells and has a white growth on top is which of the following?
A) A beta hemolyzer
B) An alpha hemolyzer
C) An organism that has hemolysins
D) An organism that ferments lactose
E) A gamma hemolyzer
F) An organism that has no hemolysins
E) A gamma hemolyzer
F) An organism that has no hemolysins
The more __________ a bacterial species has, the more likely it is to be ________.
A) virulence factors……. normal flora
B) flagella…… beneficial
C) virulence factors….. pathogenic
D) hemolysins…… beneficial
C) virulence factors….. pathogenic
Supportive media got it’s name because it contains agar, which provides a supportive surface for bacterial growth.
A) True
B) false
B) false
The bacteria growing on this Chocolate agar plate show which type of hemolysis?
A) alpha or partial hemolysis
B) gamma or no hemolysis
C) beta or complete hemolysis
D) We can not determine hemolysis using Chocolate agar, because the blood has already been lysed.
D) We can not determine hemolysis using Chocolate agar, because the blood has already been lysed.
A differential media:
A) selects for bacteria that have either a Gram(+) or Gram(-) cell wall
B) separates bacteria by size
C) supports the grow of many different types of bacteria
D) differentiates between bacteria based on metabolic processes different bacteria have
D) differentiates between bacteria based on metabolic processes different bacteria have
CNA blood agar is:
A) differential
B) supportive
C) selective
D) selective and differential
D) selective and differential
What does bacterial growth with no clearing in the agar around the growth signify on TSA-Blood media?
A) Alpha hemolysis
B) Beta hemolysis
C) Gamma hemolysis
C) Gamma hemolysis
Blood plates are incubated in a candle jar because
A) the increased humidity enhances the growth of the bacteria
B) the low amount of oxygen decreases the chance of contamination
C) the low amount of oxygen enhances the expression of blood hemolysins
D) the candle jar increases the amount of oxygen and the bacteria grow better
C) the low amount of oxygen enhances the expression of blood hemolysins
Bacteria that grow on Chocolate agar but not on other types of media are said to be:
fastidious
Crystal violet is one selective ingredient in MacConkey. What is the other selective ingredient?
bile salts
Which of the following bacteria is Gram(-)?
A) Priestia megaterium, will not grow on CNA or Mac
B) Staphylococcus aureus, grows on CNA
C) Streptococcus oralis, will not grow on Mac
D) E. coli, grows on Mac
D) E. coli, grows on Mac
An organism growing on MacConkey medium with a bright pink color change in the medium is which of the following?
A) Lacks the enzyme lactase
B) Gram(-) non-lactose fermenter
C) Cannot ferment lactose
D) Can ferment lactose
E) Has the enzyme lactase
F) Gram negative lactose fermenter.
G) Gram positive lactose fermentor
H) Not likely pathogenic
I) non-coliform
J) Is likely a pathogen
C) Cannot ferment lactose
G) Gram positive lactose fermentor
Why is the inability to ferment lactose a virulence factor?
A) Because the inability to ferment lactose means the bacteria normally line in the throat, and are therefor pathogenic.
B) Because the inability to ferment lactose means the bacteria do not normally live in the gut and therefor may be pathogenic.
C) Because the inability to ferment lactose means the bacteria normally live on the skin, and therefore are pathogenic.
D) Because the inability to ferment lactose means the bacteria are normal gut flora and therefore pathogenic.
B) Because the inability to ferment lactose means the bacteria do not normally live in the gut and therefor may be pathogenic.
The bacteria growing on the plate below produce _____________ to digest the blood in the media.
Hemolysin
CNA blood agar selects for:
A) Gram -
B) rods
C) Gram(+)
D) cocci
C) Gram(+)
D) cocci
What is the differential sugar ingredient in MacConkey Media? (The pH Indicator Neutral Red is sometimes also considered a differential ingredient.)
Lactose
What can you say aboutthis bacteria growing on MacConkey media?
A) It is Gram(+)
B) It is Gram(-)
C) It does not ferment lactose
D) It does not have blood hemolysins
B) It is Gram(-)
What does a clearing in the agar around the bacterial growth signify on TSA-Blood media?
A) Beta hemolysis
B) Alpha hemolysis
C) Gamma hemolysis
A) Beta hemolysis
Blood plates are always incubated in a ______ ___.
candle jar
If this bacteria grows on the Chocolate agar but won’t grow on TSA-blood, it is termed:
A) robust
B) normal flora
C) fastidious
D) pathogenic
C) fastidious
_________ _________ contain ingredients such as digested milk, soy, yeast or beef, which provide nutrients for growth.
Basic media
Chocolate agar medium is:
A) selective and differential
B) supportive
C) selective
D) differential
B) supportive
What advantage does the virulence factor seen in the photo give to the bacteria that have it?
A) Makes it difficult to kill the bacteria with antibiotics.
B) Allows bacteria to stick to surfaces.
C) Produces hemolysins for blood lysis.
D) Protects the DNA of the organism in a harsh environment.
D) Protects the DNA of the organism in a harsh environment.
The large, Gram(+), rod-shaped bacterium that normally lives in the soil is?
A) E. coli
B) Priestia megaterium
C) Proteus vulgaris
D) Streptococcus oralis
B) Priestia megaterium
