Same chapter3 marksDifficulty: Medium
Explain a test cross and state what it is used for.
Principles of Inheritance and Variation
3 marksDifficulty: Medium
Name three genetic disorders in human beings and state the cause of each.
Original Khojo Papers practice question — not from a past board paper.
Answer
Down's syndrome is caused by an extra copy of chromosome 21. Sickle cell anaemia is caused by a single base substitution in the gene for the beta chain of haemoglobin. Haemophilia is caused by a recessive allele on the X chromosome that prevents the formation of a clotting factor.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The first is a chromosomal disorder and the other two are Mendelian.
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