"What is a Karyotype?" -- from Chromosome18.org
A karyotype is simply a picture of a person's chromosomes. In order to get this picture, the chromosomes are isolated, stained, and examined under the microscope. Most often, this is done using the chromosomes in the white blood cells. A picture of the chromosomes is taken through the microscope. Then, the picture of the chromosomes is cut up and rearranged by the chromosome’s size.
"How Are the Chromosomes Numbered?"
Each chromosome has been assigned a number based on its size. The largest chromosome is chromosome 1.
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