1. Karyotypes and Karyotyping

2. What Are They?
A karyotype is “a visual representation of an individual’s chromosomes arranged in a specific way.” Karyotyping chromosomes involves classifying and organizing them according to the arrangement, number, size, shape, or other characteristics of the chromosomes. These pictures of an individual’s chromosomes allow scientists/doctors to identify characteristics of a person such as gender and genetic disorders, among other things.

3. How Scientists Read Chromosomes?
To "read" a set of human chromosomes, scientists first use three key features to identify their similarities and differences:
Size. This is the easiest way to tell two different chromosomes apart.
Banding pattern. The size and location of Giemsa bands on chromosomes make each chromosome pair unique.
Centromere position. Centromeres are regions in chromosomes that appear as a constriction. They have a special role in the separation of chromosomes into daughter cells during mitosis cell division (mitosis and meiosis).
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Using these key features, scientists match up the 23 pairs –
one set from the mother and one set from the father.

4. Typical Female Karyotype
46 Total Chromosomes
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5. Typical Male Karyotype
46 Total Chromosomes
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6. Monosomy X - Turner Syndrome - Karyotype
45 Total Chromosomes
One “X” Chromosome
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7. Trisomy 21- Down’s Syndrome - Karyotype
47 Total Chromosomes
Three Chromosomes at the 21st Pair
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8. XYY Karyotype 47 Total Chromosomes One “X” and Two “Y” Chromosomes
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