Use the Following to Answer Questions
the Following Microarray $\bullet$

question 63

Multiple Choice

Use the following to answer questions
The following microarray data are shown for four human genes. Two samples were hybridized to the microarray in this experiment. One sample was cDNA generated from mRNA of a tissue culture cell line that was originally derived from a B-cell leukemia. The other sample was cDNA generated from normal, mature neural tissue.
$\bullet$ Vertical stripes mean hybridization to cancerous B-cell cDNA only.
$\bullet$ Horizontal stripes mean hybridization to normal neural cell cDNA only.
$\bullet$ Completely filled in means hybridization to both cDNA types.
$\bullet$ Blank means hybridization to neither cell's cDNA.
-The gene sequences contained in spot 2 are present only in the B-cell cancer sample. What is a possible function for this gene, based on the microarray data?

• A) This gene may be involved in neurotransmitter release at the synapse since B-cells are known to be involved in cell-to-cell signaling.
• B) This gene may be involved in activating cell growth, so it is switched on in the cancer cell line that is growing rapidly.
• C) This gene is involved in the immune function of the B-cell since that is the cell type from which this cancer line was initially derived.
• D) This gene may be involved in neurotransmitter release at the synapse or in activating cell growth.
• E) This gene may be involved in activating cell growth or in the immune function of the B-cell.

---

Definitions:

Hormones

Chemical messengers produced by glands in the body that regulate the activity of cells or organs, influencing many physiological processes.

Neurotransmitters

Chemicals that transmit signals across a synapse from one neuron to another 'target' neuron.

Target Organs

Specific organs or tissues at which a drug, hormone, or other substance acts.

Transcranial Magnetic Stimulation

A non-invasive procedure that uses magnetic fields to stimulate nerve cells in the brain, often used in treating depression and other disorders.