OpenStudy (anonymous):

A woman gives birth to a son who has type AB blood. She has type B blood. Which of the following can be concluded from this about her parents' blood types? (1 point) Select one: a. One of her parents had at least one B allele. b. One of her parents had type AB blood. c. One of her parents had type B blood and the other type A blood. d. One of her parents had at least one A allele and the other at least one B allele.

4 years ago
OpenStudy (blues):

The question is about the woman, not her son. When someone has type B blood, they can have one of two possible genotypes: BB or BO. So you know she must be one of those two. Only one option is possible for her if she has one of these two genotypes...

4 years ago
OpenStudy (anonymous):

so c?

4 years ago
OpenStudy (anonymous):

or b?

4 years ago
OpenStudy (blues):

You know that her parents gave her at least one B allele. Maybe more than one. That's pretty much all you know about her.

4 years ago
OpenStudy (anonymous):

c?

4 years ago
OpenStudy (blues):

Hmm, I don't think so. The part that one of her parents has type B blood is not necessarily even true. If her parents were both AB x AB, it's possible that she would be BB if she got the B allele from both parents (hence B blood, as described) - so it's not C.

4 years ago
OpenStudy (anonymous):

so its b

4 years ago
OpenStudy (blues):

No, it's not B. One of her parent's might have had AB blood. But it could also be possible that her parents were BB or BO, in which case they would have been type B. So statement B is not necessarily true at all.

4 years ago
OpenStudy (blues):

My second response is basically a restatement of the right answer...

4 years ago