A dihybrid cross AaBb x AaBb produced 800 offspring. Predicted 9:3:3:1 yields expected counts of 450, 150, 150, 50. Observed counts are 460, 145, 152, 43. Chi-square = 1.4 (df = 3, critical = 7.82).
What conclusion is supported?
- A
The chi-square value is too small to draw a conclusion.
- B
Reject the null; the genes are linked.
- C
Reject the null; one allele is lethal.
- Dcheck_circle
Fail to reject the null; data fit the 9:3:3:1 ratio expected for independent assortment.
Explanation
Chi-square (1.4) is well below the critical value (7.82) at df=3, so observed and expected do not differ significantly. Genes appear to assort independently.