MCB LAB QUIZ 6 (ex. 6,7,8) Exam Questions And Answers 100% Verified
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1. pure culture -a culture containing a single kind of microbe
-used to determine microbial growth characteristics, pathogenicity, metabolism,
and antimicrobial susceptibility
2. selective media -contain chemicals that will partially or totally inhibit the growth of undesired
bacteria
-the growth of the desired bacteria will be enhanced
3. differential media -contain various nutrients that distinguishes one bacterium from another by their
ability to metabolize or change the media
4. Staphylococcus -this genus of microbes consists of Gram-positive bacteria and under a micro-
scope they appear as cocci (shape) and form irregular "grape-like" clusters
-part of the normal flora of skin, nasal membranes, and hair follicles
5. Methicillin-resis- staphylococci have developed drug resistance and infections caused by this
tant specific strain
Staphylococcus
aureus (MRSA)
6. catalase test -based on the fact that many microbes use oxygen to metabolize glucose in the
electron transport system and as a result produce toxic byproducts intracellularly,
such as hydrogen peroxide (H2O2).
-
7. catalase To remove hydrogen peroxide (H2O2), many cells produce what?
8. catalase breaks hydrogen peroxide down into water and oxygen gas
9. Catalase positive the observation of effervescence or bubbling
test
10. catalase false posi- weak reactions or slight bubbling
tive test
1/5
, MCB LAB QUIZ 6 (ex. 6,7,8) Exam Questions And Answers 100% Verified
Study online at https://quizlet.com/_h64n14
11. catalase test -a few drops of 3% H2O2 are added to a small sample of the colony that is rubbed
on a slide
-this test readily differentiates between Staphylococcus species (positive) and
Enterococcus or Streptococcus species (negative)
12. coagulase test most popular and widely used test to detect the presence of pathogenic Staphy-
lococcus aureus (positive) and the nonpathogenic Staphylococci (negative) such
as, Staphylococcus epidermidis
13. coagulase a bacterial enzyme that converts fibrinogen in plasma to fibrin resulting in a
visible clot
14. ethylenediaminete- preserved rabbit plasma
traacetate (EDTA)
15. bound coagulase rapidly detected by the Slide Method
(clumping factor)
16. Slide Method -performed by preparing a thick suspension of the bacterial isolate in saline on
a slide
-"clumps" will appear if the test is positive
-nonclumping samples (negative) must be further tested with a different test
17. Tube Coagulase -detects free coagulase
Test -a loopful of the isolate is mixed with a small volume (0.5 mL) of plasma in a tube
and incubated at 35-37 degrees Celsius for 4 hours
18. Tube Coagulase clot formation is detected by tilting the tube after incubation
positive test
19. Tube Coagulase if the sample did not clot after extended incubation for 24 hours, then a negative
negative test result is finally recorded
2/5
Study online at https://quizlet.com/_h64n14
1. pure culture -a culture containing a single kind of microbe
-used to determine microbial growth characteristics, pathogenicity, metabolism,
and antimicrobial susceptibility
2. selective media -contain chemicals that will partially or totally inhibit the growth of undesired
bacteria
-the growth of the desired bacteria will be enhanced
3. differential media -contain various nutrients that distinguishes one bacterium from another by their
ability to metabolize or change the media
4. Staphylococcus -this genus of microbes consists of Gram-positive bacteria and under a micro-
scope they appear as cocci (shape) and form irregular "grape-like" clusters
-part of the normal flora of skin, nasal membranes, and hair follicles
5. Methicillin-resis- staphylococci have developed drug resistance and infections caused by this
tant specific strain
Staphylococcus
aureus (MRSA)
6. catalase test -based on the fact that many microbes use oxygen to metabolize glucose in the
electron transport system and as a result produce toxic byproducts intracellularly,
such as hydrogen peroxide (H2O2).
-
7. catalase To remove hydrogen peroxide (H2O2), many cells produce what?
8. catalase breaks hydrogen peroxide down into water and oxygen gas
9. Catalase positive the observation of effervescence or bubbling
test
10. catalase false posi- weak reactions or slight bubbling
tive test
1/5
, MCB LAB QUIZ 6 (ex. 6,7,8) Exam Questions And Answers 100% Verified
Study online at https://quizlet.com/_h64n14
11. catalase test -a few drops of 3% H2O2 are added to a small sample of the colony that is rubbed
on a slide
-this test readily differentiates between Staphylococcus species (positive) and
Enterococcus or Streptococcus species (negative)
12. coagulase test most popular and widely used test to detect the presence of pathogenic Staphy-
lococcus aureus (positive) and the nonpathogenic Staphylococci (negative) such
as, Staphylococcus epidermidis
13. coagulase a bacterial enzyme that converts fibrinogen in plasma to fibrin resulting in a
visible clot
14. ethylenediaminete- preserved rabbit plasma
traacetate (EDTA)
15. bound coagulase rapidly detected by the Slide Method
(clumping factor)
16. Slide Method -performed by preparing a thick suspension of the bacterial isolate in saline on
a slide
-"clumps" will appear if the test is positive
-nonclumping samples (negative) must be further tested with a different test
17. Tube Coagulase -detects free coagulase
Test -a loopful of the isolate is mixed with a small volume (0.5 mL) of plasma in a tube
and incubated at 35-37 degrees Celsius for 4 hours
18. Tube Coagulase clot formation is detected by tilting the tube after incubation
positive test
19. Tube Coagulase if the sample did not clot after extended incubation for 24 hours, then a negative
negative test result is finally recorded
2/5
