A gene expression microarray has
A) an entire genome of DNA, cut into hundreds of pieces, attached to a small plastic or glass square.
B) short pieces of DNA of known sequence attached to a small plastic or glass square.
C) several human genes sent into bacterial cells, and the cells allowed to divide.
D) short pieces of RNA of known sequence attached to a small plastic or glass square.
E) amino acids attached to a small plastic or glass square.

Question

Quizplus · Accepted Answer

Gene expression microarrays typically use short pieces of DNA of known sequence, called probes, that are attached to a small solid support such as a glass or plastic slide. These probes are designed to hybridize with specific mRNA molecules present in a sample, allowing the quantification of gene expression levels. Option A is incorrect because microarrays do not typically involve cutting and attaching an entire genome; this would be impractical and unnecessary. Option C refers to bacterial transformation, which is not relevant to microarrays. Options D and E involve RNA or amino acids, respectively, but microarrays use DNA probes to detect mRNA levels.

A Gene Expression Microarray Has