Day4

Question 1

Gram Negative bacilli that ferment glucose, non-spore forming, facultative anaerobes. They are oxidase negative, catalase positive, gamma or beta hemolytic.30 genera and 120 species.

Answer 1

Enterobacteriaceae

Question 2

Produce pink or reddish colonies after 18-24hrs of incubation on MAC

Answer 2

Lactose fermenters

Question 3

This agar is used to differentiate between lactose and non lactose fermenting gram negative bacilli.

Answer 3

MacConkey agar

Question 4

Produce colorless translucent colonies are on MAC

Answer 4

Non-lactose fermenters

Question 5

Produce faint pink or reddish colonies after 48 hours incubation on MAC

Answer 5

Slow lactose fermenters

Question 6

True or false:

Most gram negative bacilli are found as normal flora in the intestinal tract.

Answer 6

True

Question 7

Where can gram negative bacilli be found based off of their natural habitat?

Answer 7

• salt water
• soil
• freshwater
• aquatic animals
• on plants
• most are normal human fecal flora

Question 8

True or false:

Most Fran negative bacilli are opportunistic pathogens outside the intestinal tract

Answer 8

True

Question 9

True or false:

Gram positive bacilli can be pathogenic and cause bloody diarrhea, sepsis, of cholera

Answer 9

False, negative

Question 10

True or false:

Most Enterobacteriaceae are found as normal flora in the intestinal tract.

Answer 10

True

Question 11

True or false:

Enterobacteriaceae are the most frequently encountered bacteria isolated from many clinical specimens.

Answer 11

True

Question 12

Where can Enterobacteriaceae be found based off of their natural habitat?

Answer 12

• soil
• animals
• fish
• plants
• insects
• most are normal human fecal flora

Question 13

True or false:

All Enterobacteriaceae are gram negative bacilli.

Answer 13

True

Question 14

Some Enterobacteriaceae can produce _________ or _________ which gives the organism virulence.

Answer 14

Enterotoxins or Cytotoxins

Question 15

True or false:

Enterobacteriaceae are opportunistic outside the intestinal tract.

Answer 15

True

Question 16

There are currently ___ genera and more than ____ species of Enterobacteriaceae; and ___ which are medically important.

Answer 16

30; 120;10

Question 17

Name the 10 medically important Enterobacteriaceae.

Answer 17

Citrobacter spp
Enterobacter spp.
Escherichia spp.
Klebsiella spp.
Morganella spp.
Proteus spp.
Salmonella spp.
Serratia spp.
Shigella spp.
Yersinia spp.

Question 18

Describe the microscopic appearance of Enterobacteriaceae.

Answer 18

Straight sided gram negative bacilli

Question 19

True or false:

Enterobacteriaceae can be alpha hemolytic

Answer 19

False, beta or gamma

Question 20

What Enterobacteriaceae will exhibit swarming on blood agar?

Answer 20

Proteus