Question

In a certain species of plant, the allele to produce green melons (G) is dominant over the allele to produce yellow melons (g). A student performed a cross between a plant that produced green melons and a plant that produced yellow melons. When the student observed the next generation, the 94 seeds that were produced from the cross matured into 53 plants with green melons and 41 plants with yellow melons. Calculate the chi-squared value for the null hypothesis that the green-melon parent was heterozygous for the melon-color gene.

Answer 1

Answer:

4.26

Explanation:

Let the green-melon parents be Gg, then we expect the cross with the yellow-melon plant gg so as to produce 50% Gg and other 50% of gg offspring. What we observed was that 53 green and a 41 yellow. Based on the total number of 94 offspring , we expected half and a half ratios to be 47 of each color.

                                Observed(o)   Expected(e)   (o-e)    $(o-e)^2$      $(o-e)^2/e$

Green-melon plant        53                    47               6          36             0.766

Yellow-melon plant        41                    47              -6          36             0.766

Therefore the chi-square value is 1.53 which is less than the critical value of 3.84. Therefore, the null hypothesis is accepted.