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Punnett square inheritance probability
A man and a woman do not have CF.
The man and the woman have a child who has CF.
Draw a Punnett square diagram to find the probability that their next child will have CF.
Use the symbols:
T = dominant allele t = recessive allele
Draw a ring around the genotype of any children with CF.
Probability =
Embryo screening for CF can be done by two methods.
Method 1
The woman becomes pregnant by sexual intercourse.
After 10 weeks of pregnancy a fine needle is inserted into the uterus.
A sample of the fluid surrounding the embryo is taken.
The DNA of the embryo is tested for CF.
The screening is done free by specialist hospitals for couples who are at risk of having
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What a strong answer needs
- 1 Parent genotypes
- 2 Gametes
- 3 Offspring grid
- 4 Phenotype
- 5 Probability