V. Micro 152 - Mixed Q (Pt. I)

All of the following are characteristics of Bacillus species, EXCEPT

• Grows on non-enriched media

• Most common laboratory contaminant

• Can flourish at extremes of acidity and alkalinity

• Ubiquitous

• NOTA

All of the following are characteristics of Bacillus species, EXCEPT

• Old cultures decolorize easily

• Fermentative

• Occurs singly, in pairs or in long chains

• Majority are non-pathogenic environmental organisms

• NOTA

All of the following are characteristics of Clostridium species, EXCEPT

• Requires enriched media for growth

• Fermentative

• Exhibit double zone of hemolysis

• Swarming growth on moist agar media

• NOTA

All of the following are characteristics of Corynebacterium species, EXCEPT

• Fastidious

• Facultative anaerobe

• Resembles chinese letters

• Pleomorphic

• NOTA

All of the following are characteristics of Dermatophilus species, EXCEPT

• Grow well on SDA

• Exhibit tram track appearance

• Non-acid fast, fermentative

• Facultative anaerobe

• NOTA

Answer explanation

Dermatophilus spp. do not grow on SDA

All of the following are characteristics of Erysipelothrix species, EXCEPT

• Slender, pleomorphic

• Non-acid fast, variable fermentative

• Facultative anaerobe

• Colonies are transluscent with narrow zone of incomplete hemolysis

• NOTA

All of the following are characteristics of Listeria species, EXCEPT

• Tolerates wide temp. and pH ranges

• Facultative anaerobe

• Non-motile

• Aesculin hydrolysed

• NOTA

Answer explanation

Listeria spp. are motile and exhibit tumbling motility

All of the following are characteristics of Mycobacterium species, EXCEPT

• Stained with Gram stain

• Acid fast

• Aerobic, obligate pathogens

• Environmental saprophytes

• NOTA

Answer explanation

Mycobacterium spp. often resist staining with the Gram stain, instead, Ziehl–Neelsen method is used

All of the following are characteristics of Rhodococcus species, EXCEPT

• Pleomorphic, variably acid fast

• Indole -

• Requires enriched media for growth

• Catalase + and Oxidase -

• NOTA

All of the following are characteristics of Rhodococcus species, EXCEPT

• Colonies are salmon pink in color with age

• Non-hemolytic

• Nitrate reducing

• Ferments carbohydrates

• NOTA