Question 1
Unit 1 style
Two people who both have blood group AB (genotype IᴬIᴮ) have a child. Which blood group could the child NOT have?
- Group A
- Group B
- Group AB
- Group O
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Question 2
Unit 1 style
The table describes the members of one family in which some individuals have a genetic condition. Use the table to deduce whether the allele that causes the condition is dominant or recessive. Explain your answer.
| Individual | Sex | Condition | Parents |
|---|---|---|---|
| I-1 | Male | Not affected | — |
| I-2 | Female | Not affected | — |
| II-1 | Female | Affected | I-1 and I-2 |
| II-2 | Male | Not affected | I-1 and I-2 |
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Question 3
Unit 1 style
Red-green colour blindness is caused by a recessive allele (Xᵇ) on the X chromosome. A man with normal colour vision and a woman who is a carrier of the allele plan to have a child. Draw a genetic diagram and give the probability that their first child is a colour-blind boy.
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Question 4
Unit 1 style
Explain how a mutation in the gene for the CFTR protein leads to the symptoms of cystic fibrosis in the gaseous exchange system and the digestive system.
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Question 5
Unit 1 style
Compare and contrast amniocentesis and chorionic villus sampling.
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Question 6
Unit 1 style
A couple who are both carriers of the cystic fibrosis allele decide to have a child by IVF with pre-implantation genetic diagnosis (PGD). Describe how PGD is carried out.
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Question 7
Unit 1 style
Discuss the ethical and social issues relating to prenatal genetic screening, from religious, moral and social viewpoints.