Question
The pedigree below shows two generations of individuals within a family. The pedigree shows that one daughter has a genetic trait, even though neither of her parents nor her siblings have the trait.
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How can this daughter have the genetic trait if no one else in her family has it?
A.
The trait is not inherited.
B.
The trait is determined by a recessive allele that both parents carry.
C.
The trait is passed only from female to female.
D.
The trait is determined by a dominant allele that both parents carry.
Image
How can this daughter have the genetic trait if no one else in her family has it?
A.
The trait is not inherited.
B.
The trait is determined by a recessive allele that both parents carry.
C.
The trait is passed only from female to female.
D.
The trait is determined by a dominant allele that both parents carry.
Answers
GPT-4o mini
The best explanation for how the daughter can have a genetic trait when neither of her parents nor her siblings have it is:
**B. The trait is determined by a recessive allele that both parents carry.**
In this case, both parents may be carriers of a recessive allele for the trait, meaning they each have one dominant allele (which does not express the trait) and one recessive allele. Therefore, they can have one child (the daughter) who inherits the recessive allele from both parents, expressing the trait.
**B. The trait is determined by a recessive allele that both parents carry.**
In this case, both parents may be carriers of a recessive allele for the trait, meaning they each have one dominant allele (which does not express the trait) and one recessive allele. Therefore, they can have one child (the daughter) who inherits the recessive allele from both parents, expressing the trait.