a man with blue eye married a girl with broun eye and the mother of the girl has blue eye. What is the probability that their children will have blue eye
It has been taught to millions of high school students that it is two genes, nowadays, a few teachers (I hope yours) is teaching that eye color is much more complicated, and two genes are required:
http://genetics.thetech.org/sites/default/files/EyeColorChart2.gif
the man obviously is bb bb.
The wife can be to have brown eyes
BB GG
BB Gb
BB bb
Bb GC
Bb bb
but the mom of the girl was blue eyed, so she was bb bb.
which tells me then the wife with brown eyes, has to be Bb bb or BB bb.
if this wife and the man has kids, then we are crossing bb bb X Bb bb (or BB bb)
in case Dad is Bb bb, then the kids can be bb bb or Bb bb . You can pundett those possibilites out. IF the man is BB bb, then the children must be Bb bb, all brown eyed. so blue eyed kids vs brown eyed: 50:50 chance. Pundett them out.
http://genetics.thetech.org/how-blue-eyed-parents-can-have-brown-eyed-children
To determine the probability that the children of the man and woman will have blue eyes, we need to consider the genetic factors involved. The information provided in the question suggests that the blue-eyed trait is present in both the man and the girl's mother.
In terms of eye color inheritance, it is generally understood that the brown eye color trait is dominant, while blue eye color is recessive. This means that if an individual carries one allele for brown eyes and another for blue eyes, the brown eye color will be expressed. However, if an individual carries two alleles for blue eyes, the blue eye color will be expressed.
Based on this information, we can assume that the man has two alleles for blue eyes (since he has blue eyes), while the girl's mother has one allele for blue eyes (since she has brown eyes but carries the blue eye allele).
Now, let's examine the possible combinations of the alleles for the children:
1. The man can pass either his blue eye allele or his blue eye allele to the children (since blue is recessive, he only carries blue alleles).
2. The girl can pass either her blue eye allele or her brown eye allele to the children (since she carries both blue and brown alleles).
The probability of each event occurring is 50% since both the man and woman can pass on only one type of allele.
Let's consider the possible outcomes for eye color:
1. If the man passes his blue eye allele (100%) and the girl passes her blue allele (50%), the child will have blue eyes (100% * 50% = 50%).
2. If the man passes his blue eye allele (100%) and the girl passes her brown allele (50%), the child will have brown eyes (100% * 50% = 50%).
So, based on this analysis, the probability that their children will have blue eyes is 50%.
It is important to note that this is a simplified explanation, as eye color inheritance can be influenced by more complex genetic factors.