A Cluster of Cases of Legionellosis Have Occurred in Your

question 13

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.

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Definitions:

Price-Support Program

Government policies designed to maintain the price of a commodity at a certain level through subsidies or purchase of the market surplus.

Price Supports

Government interventions to maintain the market price of a commodity at a certain level to protect producers from market fluctuations.

Price Floor

A government or regulatory-imposed minimum price for a commodity or service, intended to prevent the market price from falling below a certain level.

Price Ceiling

A government-imposed limit on how high a price can be charged for a product, service, or commodity, usually intended to protect consumers.