Two Strains of E

question 60

Multiple Choice

Two strains of E.coli-one of which can turn on its lactase production and one that cannot-are grown together with lactose in the medium.If all other conditions are equal,what will occur?

• A) Both strains will continue to be present in equal amounts.
• B) The two strains will kill each other off.
• C) The strain that can turn on lactase production will overgrow the culture and be the only one left.
• D) The strain that cannot turn on lactase production will overgrow the culture and be the only one left.
• E) The strain that can turn on lactase production will make its own lactose once the lactose present in the medium is completely used.

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Definitions:

Fatty Acids

Long chains of hydrocarbon molecules with a carboxylic acid group, which are components of lipids and play roles in energy storage and cellular structure.

Potassium Ion

A positively charged ion (K+) essential for various biological processes, including nerve transmission and muscle contraction.

Simple Diffusion

The movement of molecules from an area of higher concentration to an area of lower concentration without the need for energy input or assistance of membrane proteins.

Cellular Membrane

The cellular membrane, or plasma membrane, is the biological membrane that separates the interior of all cells from the outside environment, controlling the movement of substances in and out of cells.