Question

Uncle Smiley is heterozygus for a yellow face, married a woman with a green face.Both of them always wanted a large family! If they were to have 12 children, what are the probability that the children would have yellow faces? How many would have green faces? Create a Punnett square to help you find your answer

Answer 1

When a heterozygous yellow-faced person (Yy) has children with a green-faced person (yy), there's a 50% chance for each child to have a yellow face (Yy) or green face (yy), with an expected ratio of 6 yellow to 6 green faces among 12 offspring.

Step-by-step explanation:

Uncle Smiley, who is heterozygous for a yellow face, when crossed with a woman with a green face, produces offspring with either yellow or green faces based on Mendelian genetics. A heterozygous yellow face can be represented as Yy where Y represents the dominant yellow allele and y represents the recessive green allele. If Uncle Smiley's genotype for face color is Yy and his wife's genotype is yy, each child's face color is determined by one allele from each parent.

Using a Punnett square, we can predict the outcomes for their children. The square would show that there is a 50 percent chance for a child to have a yellow face (Yy) and a 50 percent chance for a child to have a green face (yy). Therefore, for 12 children, we would expect about 6 with yellow faces and 6 with green faces, though actual results may vary due to random assortment of alleles.

Answer 2

The probability that the children would have yellow faces is ½. Six children would have green faces.

Step-by-step explanation:

It is given here that uncle smiley is heterozygous for yellow face. If an individual is heterozygous for a trait then it will be the dominant trait that will be expresses. Thus the dominant trait here is yellow face.

The wife has green face which means that she is homozygous recessive since she expresses the recessive trait. Let the letter Y represent the dominant yellow and letter y represent the recessive trait green. The trait can be represented as

`Yy * yy`

Yy Yy yy yy

Yellow yellow green green

It is clear from the cross that half of the individuals will have yellow face and half will have green face. Thus if the couple has 12 children the probability that the children have yellow faces will be 1/2.

6 children would have green faces.