Term
| Of what morphology are most bacteria possessing flagella? |
|
Definition
|
|
Term
| What are the Gram reactions of Clostricium and Bacillus? |
|
Definition
|
|
Term
| How might a capsule contribute to pathogenicity? |
|
Definition
| capsules allow them to escape phagocytosis |
|
|
Term
| How might flagells contribute to pathogenicity? |
|
Definition
| Flagella make bacteria motile and allow them to spread on their own. |
|
|
Term
| Of what advantage to Clostridium is an endospore? |
|
Definition
| When conditions are unfavorable, the formation of an endospore allows teh bacteria to remain in a dormant state until conditions become favorable. |
|
|
Term
| What prevents the cell from appearing green in the finished endospore stain? |
|
Definition
| Excess dye is washed out of the cell by deinonized water, leaving it colorless until the application of the counterstain. and the application of safranin, turns the cell pink. |
|
|
Term
| The flagella stain uses crystal violet, as does the Gram stain. Why do all cells stain purple in the flagella stain but not in the Gram stain? |
|
Definition
| the gram stain procedure uses a decolorizer to differntiate between Gram + and Gram- cells. |
|
|
Term
| How would an endospore stain of Mycobacterium appear? |
|
Definition
| All green, as steaming makes the walls permeable to malachite green. Mycobacterium do not have endospores. |
|
|
Term
| What type of culture medium would increase the size of a bacterial capsule? |
|
Definition
| One high in carbohydrates, glucose or sugars (polysccharides) |
|
|
Term
| Describe the microscopic appearance of encapsulated Streptococcus if stained with safranin and nigrosin. |
|
Definition
| The safranin would stain the bacteria red. Nigrosin is a negative stain and will stain the background leaving the capsule colorless. |
|
|
Term
| In the Dorner endospore stain, a smear covered with carbolfuchsin is steamed, then decolorized with acid-alcohol and counterstained with nigrosin. Describe the microscopic appearance after this procedure. |
|
Definition
| Carbolfuchsinwill leave the endospores red or pink, the nigrosin will make the background dark. So it will be a colorless cell with pink endospores and a dark background. |
|
|
Term
| Endospores appear as colorless areas in a simple stain and Gram stain. Why is it necessary to perform an endospore stain to identify Clostridium difficile in health care settings? |
|
Definition
| Colorless areas could be something beside endospores. The endospore stain will confirm it as an endospore. |
|
|
Term
| How could the procedures used i exercise 24 be altered to measure bacteriostatic effects? |
|
Definition
| Mix the bacteria with the chemical, then subculture in chemical free media. If there is any growth then itiis bacteriostatic. If there is no growth, then it is bacteriocidal. |
|
|
Term
| Is the disk-diffusion technique measuring bacteriostatic or bactericidal activity? |
|
Definition
| Bacteriostatic, until we can perform a subculture to determine if it is bacteriocidal. |
|
|
Term
| In which growth phase is an organism most sensitive to an antimicrobial agent? |
|
Definition
|
|
Term
| Why is the disk-diffusion technique not a perfect indicationof how the drug will perform in vivo? What other factors are consdered before using the antimicrobial agent in vivo? |
|
Definition
| Other factors contribute to performance in vivo. These include, variations in PH, patient nutrition, side effect, other medical conditions, additional drug interactions. |
|
|
Term
Ampicillin
type of microbial agent and method of action? |
|
Definition
semisynthetic penicillin
Broad based
inhibits cell wall synthesis |
|
|
Term
Erythromycin
Type of antimicrobial agent and method of action? |
|
Definition
Macrolide
inhibits protein synthesis |
|
|
Term
Penicillin G
Type of antimicrobial agent and method of action? |
|
Definition
Natural penicillin
inhibits cell wall synthesis |
|
|
Term
Streptomycin
type of antimicrobial agent and method of action |
|
Definition
Aminoglycoside
inhibits protein synthesis |
|
|
Term
Tetracycline
Type of antimicrobial agent and method of action? |
|
Definition
tetrocyclines
broad based
inhibits protein synthesis |
|
|
Term
vancomycin
Type of antimicrobial agent and method of action? |
|
Definition
polypeptide antibiotic
inhibits cell wall synthesis |
|
|
Term
| What effect would the presence of tetracycline in the body have on penicillin therapy? |
|
Definition
| tetracyclin is bacteriostatic. Penicillin would have no effect, because penicillin inhibits cell wall synthesis and without growth there is no cell wall synthesis to inhibit |
|
|
Term
| What is a surgeon trying to accomplish with a a 10-minute scrub with a brush followed by an antiseptic? |
|
Definition
| To remove transient and resident microbiota |
|
|
Term
| How do transient and normal microbiota differ? |
|
Definition
| transient microbiota are temporary and normal is permanent |
|
|
Term
| What is the schaeffer-fulton stain |
|
Definition
|
|
Term
|
Definition
1. prepare smear with heat fixing
2. cover with paper towel
3. cover with malachite green
4. steam for 5 minutes
5. wash with water
6. cover with safranin for 30 seconds
7. wash with water
blot |
|
|
Term
|
Definition
1. loopful of Congo red
2. gently mix bacteria in Congo red
3. let air dry
4. cover with acid alcohol for 15 seconds
5. wash with water
6. cover with acid fuchsin for 1 minute
7. wash with water
Blot |
|
|
Term
|
Definition
1. start with scrupulously clean slides
2. drop of distilled water
3. carefully touch a loopful of bacteria to water drop
4. tilt slide to spread water drop
5. air dry
6. cover dried smear with flagella stain(crystal violet) for 4 minutes
7. rinse
let air dry |
|
|
