Bacteria

Question 1

Pt has swelling of submandibular, tenderness. Pt is alcoholic. Radiographic-mass radiopaque (sialolith)-circumscribed, 1 cm x 1 cm, what is the reason for swelling?

Answer 1

Bacterial infection

Question 2

Best method for bacteria to replicate & transfer most genetic information?

Answer 2

Conjugation = plasmid DNA transfer

• Transformation = bacteria takes up extracellular donor DNA
• Transduction = donor DNA packed into virus (bacteriophage) that infects the bacteria (1 step)

Question 3

Action of the pilli in organisms pathogenicity?

Answer 3

Attachment & adherence to host cells

Question 4

Difference between staph and strep?

Answer 4

Staph has catalase enzyme which gets rid of H₂O₂

Question 5

Lancefield grouping is a serotype classification (describing specific carbohydrates present on the bacterial cell wall), what is used to classify?

Answer 5

B-hemolytic Strep

Determined by the C-carb composition of the cell wall

Question 6

Streptomycin inhibits what?

Answer 6

Protein production (translation)

Question 7

What aspect of Staph is responsible for food poisoning?

Answer 7

Enterotoxin

Question 8

MOA of staph aureus for drug resistance?

Answer 8

Produces enzyme that breaks down penicillin, beta lactamase

Question 9

What bacteria causes endocarditis in IV drug user?

Answer 9

Staph Aureus

Question 10

Most common type of Endocarditis?

Answer 10

Streptococcus Viridian (α-hemolytic strep)

Acute→ Staph
Subacute which is more common is Viridans

Question 11

Which of the follow disease has Janeway lesions?

Answer 11

Infective Endocarditis

Question 12

Which toxin produces scarlet fever?

Answer 12

Erythrotoxin (pyrogenic exotoxin)

Question 13

Rash for Scarlett Fever

Answer 13

Erythrogenic Toxin of Group A Beta Hemolytic S. pyogenes

Question 14

Strep mutans produces?

Answer 14

Dextran

Which is glucose linked in alpha 1,6 linkage

Question 15

What enzyme do oral bacteria use to create dextran & participates in bacterial aggregation on teeth?

Answer 15

Glucosyltransferase

Question 16

What enzyme primarily breaks down sucrose?

Answer 16

Glucosyltransferase (dextran sucrase)

Question 17

Streptococcus breaks down sucrose into what products?

Answer 17

Glucose + Fructose

• Glucans → Dextrans + Mutans + Levans

Question 18

Dextrans are polymers of?

Answer 18

Glucose

• Dextrans + Mutans are polymers of Glucose
• Levans are polymers of Fructose

Question 19

How is glucose and fructose associated with caries?

Answer 19

Dextrans and levans

Question 20

Which of the following is not an oral bacterium & not found in dental plaque?

Answer 20

Strep pyrogens

Question 21

Which of the following does NOT cause pneumonia:

a. Strep mutans
b. H influenza
c. S pneumoniae

Answer 21

Strep mutans

Question 22

Most common bacteria on the dorsum of the tongue?

Answer 22

S. salivarius

Question 23

Lipid A with a polysaccharide core is in which organism?

Answer 23

Gram negative bacteria

Question 24

Gram negative bacteria have …
Gram positive bacteria have …

Answer 24

lipopolysaccharides (LPS)

teichoic acids

Question 25

N-Muramic acid is part of?

Answer 25

**Bacterial Cell Wall** * It occurs naturally as N-acetylmuramic acid in peptidoglycan * Function is a structural component of bacterial cell walls. * Chlamydia has none.

Question 26

Glycan binds what in bacterial cell wall?

Answer 26

D-alanine

Question 27

Rickettsia is a ...

Answer 27

* gram-negative * nonspore-forming * highly pleomorphic bacteria responsible for : **Typhus**

Question 28

Rickettsia diseases are destructive for/target?

Answer 28

**Endothelial cells of capillaries** * Rickettsia are small, gram (-), aerobic coccobacillary bacteria

Question 29

Which one needs arthropods vector (insects) or fleas?

Answer 29

**Rickettsia** except Coxiella burnetii

Question 30

Weil Felix test is used for?

Answer 30

Test for Rickettsial infections

Question 31

Which is not from an insect/flea bite?

Answer 31

Q Fever Cox burn

Question 32

Etiology of Q fever

Answer 32

**Coxiella burnetii** (can be in salivary gland) also **CMV** can be in salivary gland as well

Question 33

The toxin of the gas gangrene organism has what kind of the enzymatic activity?

Answer 33

(C. perfringens) Lipase lecithinase

Question 34

Clostridium Tetani are all the following EXCEPT... * Gram-Positive * Anaerobic * Spores * Rod-shaped

Answer 34

No exception

Question 35

Mechanism of action of the tetanus toxin?

Answer 35

Inhibition of neurotransmitter release (prevent release of GABA and Glycine)

Question 36

Over-treating with antibiotics, C. difficile, would show?

Answer 36

Pseudomembranous Colitis (?) * Clostridium difficile causes diarrhea & intestinal colitis. CLINDAMYCIN

Question 37

Clostridium and bacillus are ( ) bacteria

Answer 37

spore-forming

Question 38

What ion is related to the heat resistance of the endospore?

Answer 38

Calcium dipicolinic

Question 39

Mycobacterium Tuburculosis has ( ) that block ( ) from penetrating.

Answer 39

mycolic acid antibiotics

Question 40

Legionnaires pneumophila is mainly found in ( ) because it prefers ( ).

Answer 40

air-conditioning systems aerosolized water

Question 41

An infection of the epithelial cells of the eye that can sometimes enter back into the nasopharynx. This bacteria can also cause blindness.

Answer 41

Trachoma due to Chlamydia trachomatis

Question 42

Most common cause of non-gonococcal urethritis.

Answer 42

Chlamydia

Question 43

Bacillary dysentery is caused by ( )

Answer 43

Shigella (Shigellosis)

Question 44

Bacillus anthracis produces what 3 toxins?

Answer 44

* PA - protective antigen * EF - edema factor * LF - lethal factor

Question 45

Treponema pallidum, spirochete bacteria is visualized by ( ).

Answer 45

Dark-field microscopy

Question 46

CN VII deafness, Hutchinson's incisors, and mulberry molars are all indicative of ( ).

Answer 46

Congenital syphilis

Question 47

What protozoa are spread in cat feces?

Answer 47

Toxoplasma gondii