Genes relating to albinism are denoted by A, and a. Those who recieve a from both parents will be albino. Those who carry A,a are known as carriers. Suppose that a normal couple has two children exactly one of whom is an albino. Suppose that the nonalbino child mates with a person who is know to be a carrier.
(a) What is the probability that their first offspring is an albino?
(b) What is the conditional probability that thery second offspring is an albino given that their firstborn is not?
2007-02-19 18:00:38 · 3 answers · asked by mathHelpless 1 in Science & Mathematics ➔ Biology
Prob (non-albino child is carrier ie. Aa) = 2/3
Prob (non-albino's child inherits a) = 1/3
Prob (carrier's child inherits a) = 1/2
a) Prob (first offspring albino) = 1/2 * 1/3 = 1/6
Second problem
Prob (non-albino aA) = 3/5
Prob (second normal) = 2/5 + 3/5 *3/4 = 17 /20
b) Prob (second albino) =3/20
2007-02-19 18:37:38 · answer #1 · answered by mustafa 2 · 0⤊ 0⤋
Don't listen to the first answer, it's wrong.
He's correct in saying that there is a 2/3 chance that the nonalbino child will be a carrier. After that things go awry.
The potential carrier is married to a known carrier. The second parent by definition is Aa.
So if both parents are carriers, you have a 1/4 chance of the first offspring being albino. But there is only a 2/3 chance that parent number 1 is a carrier, so we have to multiply the probabilities:
2/3 x 1/4 = 2/12 = 1/6
The probability for the second child to be an albino is exactly the same as the probability for the first: 1/6
2007-02-20 00:12:32 · answer #2 · answered by floundering penguins 5 · 0⤊ 2⤋
Your anticipated consequences would impact the way you turn the second one coin. In gene inheritence the randomeness occurs mutually two times one time at the same time as a cellular makes 4 random sperms and again at merging sperm with egg.
2016-12-04 10:00:12 · answer #3 · answered by ? 4 · 0⤊ 0⤋