Activity: Analysis of Human Karyotypes
Aim:
To learn how to recognise male and female karyotypes and also the chromosome anomaly
‘trisomy 21’ which results in Downs Syndrome.
Introduction
Important chromosome “pairs”
Most human chromosomes are found as
homologous pairs.
The sex chromosomes are
 Xy in males and
 XX in females.
Occasionally something goes wrong and
three copies of a chromosome are
inherited. A common example of this is
trisomy 21.
Female XX
Male XY
trisomy
Activity - To do
Look carefully at the karyotypes below, identify the gender of the person, and look for any examples
of trisomy. Complete notes about each karyotype in the box.
Karyotype
Analysis
This a computer generated SKY (spectral karyotype)
© David Faure, InThinking www.biology-inthinking.co.uk
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Activity: Analysis of Human Karyotypes
Images: Wiki commons
© David Faure, InThinking www.biology-inthinking.co.uk
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