Lesson 2 -Karyotyping
Lesson Objectives
Description of methods used to obtain cells for karyotype analysis e.g. chorionic villus sampling and amniocentesis and the associated risks.
Non-disjunction can cause Down syndrome and other chromosome abnormalities.
Studies showing age of parents influences chances of non- disjunction.
Use of karyograms to deduce sex and diagnose Down syndrome in humans.
A karyogram shows the chromosomes of an organism in homologous pairs of decreasing length.
Activites
Activity 1 - Read through the lesson summary
Activity 2 - Creating Karyotypes and identifying non-disjunctions.
Instructions
1. Pick one of the 7 different chromosome sets located here.
2. Each of the karyotypes is on a document. You need to arrange the chromosomes, pairing up each homologous chromosome.
3. Each of you will have a disorder. Once you have identified the disorder, you will need to write a short summary of the disorder.
Activity 3 - Non-disjunction
Mismatches in chromosome numbers occur to errors in meiosis. Briefly describe how a non-disjunction can occur.