An Rh negative woman is married to an Rh positive man whose father was also Rh negative. What are the chances that their child will be affected?
Correct answer: B. 50%
- A. 25%
- B. 50%
- C. 75%
- D. 100%
Explanation
Given that that man's father was Rh-negative and man is Rh-positive,the man must be heterozygous for Rh-positive. Rh negative woman should be homozygous as recessive allele only expresses itself in homozygous condition. There is a fifty percent chance of being "affected" with Rh negative phenotype as shown:
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? [email protected]
About Inheritance
Mendel's laws explain segregation, independent assortment and the prediction of genetic ratios using alleles, genotypes and phenotypes. The chapter also covers linked genes, recombination and crossing over during meiosis, then applies pedigree reasoning to X-linked recessive traits, which show different inheritance patterns in males and females.
Practise Inheritance
1,238 free Inheritance MCQs from Biology, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Discussion
Stuck on an option, or know a faster way to get there? Ask or explain it here.
No comments yet. Be the first to explain this one.
Exams that ask Biology questions like this
Biology is on 8 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
More Inheritance questions
A man who has type AB blood cannot father a child with type _ blood, because he would pass on either the _ or the B allele to all of his offspring.
Pick the correct option about Drosophila.
The law of dominance is illustrated in the garden pea by:
The gene for ABO-blood group systems in humans is represented by symbol
A woman is a carrier for a sex linked disorder. She marries a man whose father had the disorder, and whose mother did not. The man is unaffected. If they have a child, what is the probability that the child is also a carrier?
If the gene expresses itself then its penetrance is?