The Graph Below Shows a Growth Curve of E

question 26

Multiple Choice

The graph below shows a growth curve of E. coli growing in a defined medium containing equal molar amounts of glucose and lactose. Based on your knowledge of the regulation of the lac operon, the best explanation of these results is that

• A)the bacteria are utilizing both sugars simultaneously.
• B)early on, due to the presence of lactose, the bacteria utilize the lac operon. Glucose is used later.
• C)the presence of glucose causes the formation of cAMP catabolic repressor protein (CR
• P)complexes, which shut down the lac operon until the glucose is used up.
• D)glucose is used first. Once glucose becomes limiting, intracellular cAMP increases, forming cAMP- CRP complexes that activate the lac operon to use lactose.
• E)none of the above

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Definitions:

Debit Portion

The side of an accounting entry that increases asset or expense accounts or decreases liability, equity, or revenue accounts.

Asset Account

A category in accounting ledgers that records the increases and decreases in specific assets owned by a business.

Liability Account

An account on a company's balance sheet representing debts or obligations that the company owes to others.

Revenue Recognition Principle

An accounting principle that dictates the conditions under which revenue is recognized and recorded, usually when it is earned and realizable.