You Are Interpreting Data on a DNA Chip or Microarray

question 16

Multiple Choice

You are interpreting data on a DNA chip or microarray. You expose the chip to a mixture of two cDNA populations: one from cells that were not treated with a glucocorticoid hormone (untreated controls; labeled with a red fluorescent dye) and a population from cells that were treated with glucocorticoid hormones (glucocorticoid-treated; labeled with green fluorescent dye) . You look at a spot on the chip representing the gene for phosphofructokinase, a gene that is not affected by glucocorticoid treatment, but is instead expressed in all cells. What color should the spot representing the phosphofructokinase gene be?

• A)red
• B)green
• C)yellow
• D)no color, the spot is not labeled
• E)brown

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Definitions:

Datum Axis

An imaginary line or surface referenced in manufacturing or inspection of parts and assemblies to ensure coordination and correctness of dimension and tolerance specifications.

Circular Runout

A tolerance that controls the uniformity of a feature's surface as it is rotated about a datum axis.

Eccentricity

Eccentricity refers to the degree to which a geometric shape’s center does not align with a reference axis or point, crucial in designing rotating parts to minimize imbalance.

Cylindricity

A form tolerance that defines how much a cylindrical feature's actual profile may deviate from a perfect cylinder.