A rough black guinea pig bread with a rought white one and gives 28 rough black 31 rough white 11 smooth black and 10 smooth white. What are genotype of parents? test the validity of your answer by chi-square method
Answers
Answer: Representing the genotypes.
R-rough
r-smooth
B-black
b-white.
Predicted genotypes of parents are
RrBb and Rrbb
Dihybrid cross between the two for 1st generation gives.
Rough black: 6
Rough white:6
Smooth black:2
Smooth white:2
From the question, total number of offspring is 80.
Total number from dihybrid cross is 16.
To get the factor for multiplying the offspring, divide 80 by 16 which gives 5.
So, multiply all the offspring from dihybrid cross by 5 which then gives.
Rough black:30
Rough white:30
Smooth black:10
Smooth black:10
Sum is 80 offsprings.
Proof using chi-square method for the 4 classes.
The image shows the working out.
Chi-square value is low and shows a probability of 90% from other calculation. A very low value means that our prediction is actually correct and the deviation is small.
Therefore, the genotypes of the parents are
RrBb and Rrbb
