A Strain of E

question 20

Multiple Choice

A strain of E.coli is trp^{− his− lac−}.Which medium would this bacterium grow on?

• A)minimal medium with lactose as the sugar, supplemented with histidine and tryptophan
• B)minimal medium with glucose as the sugar, supplemented with histidine and tryptophan
• C)minimal medium with glucose and lactose as the sugar
• D)minimal medium with glucose as the sugar

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Definitions:

External Benefit

A positive effect on a party who did not choose to incur that benefit, often associated with public goods or services.

Public‐spirited

Exhibiting a selfless concern for the well-being of the community and the willingness to act for the public good.

Air Pollution

The presence of substances in the atmosphere that are harmful to the health of humans and other living beings or cause damage to the climate or materials.

Medical Care

Services provided by healthcare professionals to diagnose, treat, or prevent diseases and injuries in individuals.