Multiple Choice
A cluster of cases of legionellosis have occurred in your neighborhood. People with the illness have cough, fever, shortness of breath, chest pain and sometimes diarrhea. The illness is caused by the bacterium Legionella pneumophila, a facultative intracellular parasite that survives in certain ameba. The organism has an absolute requirement for L-cysteine.
-In some labs, samples containing suspected L. pneumophila are cultured on traditional BCYE medium as well as BCYE medium lacking L-cysteine. How would L. pneumohila be identified in this situation?
A) Compare the two plates. Colonies that grow on traditional BYCE medium but not on BYCE medium lacking cysteine are likely L. pneumophila.
B) Compare the two plates. Colonies that grow on BYCE medium lacking cysteine but not on traditional BYCE medium are likely L. pneumophila.
C) Compare the two plates. Colonies that grow on both traditional BYCE medium and on BYCE medium lacking cysteine are likely L. pneumophila.
D) Compare the two plates. Colonies that do not grow on traditional BYCE medium or on BYCE medium lacking cysteine, but do grow on nutrient agar are likely L. pneumophila.
E) Compare the two plates. Colonies that grow on traditional BYCE medium and are blue, yellow or cyan in color are likely L. pneumophila.
Correct Answer:

Verified
Correct Answer:
Verified
Q8: The solidifying agent used most successfully in
Q9: The simplest technique for isolating bacteria in
Q10: Products that limit pH changes are often
Q11: Late log phase of the bacterial growth
Q12: During which phase of growth are bacteria
Q14: In the cultivation of microaerophilic and anaerobic
Q15: A halophilic, aerobic mesophile has a generation time
Q16: In a rapidly multiplying bacterial population, cell
Q17: It is assumed that every colony observed
Q18: The lag phase of the bacterial growth