If There Are Mutations That Inactivate LacP and LacI, Which

question 3

Multiple Choice

If there are mutations that inactivate lacP and lacI, which of the following statements is true? (I = lac repressor gene; Z, Y, A = lac operon structural genes; P = lac promoter; O = lac operator)

• A) These are mutations that are, respectively, cis- and trans-acting on lac operon expression.
• B) These are mutations that are, respectively, trans- and cis-acting on lac operon expression.
• C) These will affect the expression of I only.
• D) These will affect the expression of only Z, Y, and A.
• E) These mutations will have no effect.

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Definitions:

Color Constancy

The ability of the human visual system to perceive colors of objects, invariant to the color of the light source.

Brain Region

Specific areas within the brain that are responsible for different functions, such as the hippocampus for memory or the frontal lobes for decision making.

Off-Surround Cell

A type of neuron in the visual system that is inhibited when light falls on its surrounding area, enhancing contrast detection.