Blood smears, blood agar, and antimicrobial disk diffusion Quiz

Question 1

IN the disk diffusion test, the ____ of the zone of inhibition is measured and used for interpretation

Answer 1

diameter

Question 2

which of the following is recommended for inocula preparations in antibiotic susceptibility testing?

Answer 2

four to five colonies diluted to a McFarland 0.5 standard turbidity

Question 3

the turbidity of a McFarland 0.5 standard corresponds to approx. ________ bacteria per milliliter

Answer 3

1.5 x 10^8

Question 4

disk diffusion methods used to measure

Answer 4

antibiotic susceptibility

Question 5

what type of media is blood agar

Answer 5

differential

Question 6

which of the following statements is true regarding Streptolysin S and O

Answer 6

Streptolysin S is oxygen-stable, while Streptolysin O is oxygen-labile

Question 7

which term is used when a microorganism growing on blood agar incompletely lyse erthrocytes?

Answer 7

Alpha hemolysis

Question 8

what information does a colony-forming unit (cfu) provide?

Answer 8

number of viable bacteria on the agar were able to grow into colonies

Question 9

which of the following is the primary purpose of a blood smear analysis?

Answer 9

to assess the size, shape, and the quantity of blood cells

Question 10

identify the cell (BIG, purple, light purple with big dark center)

Answer 10

monocyte