2. The lack of pigmentation, called albinism, in humans is...

2. The lack of pigmentation, called albinism, in humans is the result of a recessive allele (a) and normal pigmentation is the result of its dominant allele (A). Two normal parents have an albino child. Determine the probability that: a) The next child is albino b) The next 3 children are albinos 6 pts.

Transcript

00:01 The lack of pigmentation called albinism in humans is the result of a recessive allele.

00:08 And normal pigmentation is the result of its dominant allele a.

00:12 Two normal parents have an albino child.

00:16 Determine the probability that the next child is albino.

00:21 So first we need to do a punnet square.

00:26 And it tells us that we have two normal parents, which means that each of them have at least one dominant allele.

00:36 Because if they did not have a dominant allel, then they would be albino themselves.

00:43 Albinosism is recessive.

00:45 So in order for that to show both alleles have to be recessive.

00:50 Because just like the parents, if there is at least one dominant allele, then the phenotype would not be albinolism.

00:58 So these two normal parents, parents have an albino child.

01:04 So that tells us that the parents have to have that recessive allele.

01:08 Otherwise, there was no possible way for them to have an albino child.

01:14 So that tells us that each parent is heterozygous.

01:18 Because when you finish out the punnet square, we have this offspring right here, which is homozygous recessive, and that would be the albino child.

01:31 Because all three other offspring will not be albino because they all have at least one dominant allele.

01:40 So now it's asking for the probability that the next child is albino...

Question

Please give Ace some feedback