2. In corn, purple kernels (P) are dominant over yellow kernels (p) and full kernels (F) are dominant over shrunken kern
Posted: Thu Jun 09, 2022 1:56 pm
2. In corn, purple kernels (P) are dominant over yellow kernels
(p) and full kernels (F) are dominant over shrunken kernels (f). In
a parental cross, a corn plant having purple and full kernels is
crossed with a plant having yellow and shrunken kernels and the
following progeny are obtained: purple, full 112 purple, shrunken
103 yellow, full 91 yellow, shrunken 94
(a) What are the most likely GENOTYPES of the parents? Hint:
Since I have already given you which characteristic is dominant and
recessive, based on the numbers of progeny for each characteristic,
can you figure out what the genotypes of the parents must have been
to create those numbers in the progeny? The best way to begin this
problem might be to break the cross down into simpler monohybrid
crosses for a single characteristic (seed color, purple vs yellow
and seed shape, full vs shrunken).
(b) Now that you have what you think are the most likely
parental genotypes, what are the likely EXPECTED RATIOS from the
parental cross? Based on this ratio, what are the expected
proportions for each type of progeny?
(c) Test your hypothesis with a chi-square test and show your
calculations below. As usual, be sure to clearly state (1) the
calculated chi-square value, (2) the degrees of freedom, (3) the
probability associated with the calculated chi- square value, and
(4) whether you fail to reject or reject the null hypothesis
(written out in a full sentence)
(p) and full kernels (F) are dominant over shrunken kernels (f). In
a parental cross, a corn plant having purple and full kernels is
crossed with a plant having yellow and shrunken kernels and the
following progeny are obtained: purple, full 112 purple, shrunken
103 yellow, full 91 yellow, shrunken 94
(a) What are the most likely GENOTYPES of the parents? Hint:
Since I have already given you which characteristic is dominant and
recessive, based on the numbers of progeny for each characteristic,
can you figure out what the genotypes of the parents must have been
to create those numbers in the progeny? The best way to begin this
problem might be to break the cross down into simpler monohybrid
crosses for a single characteristic (seed color, purple vs yellow
and seed shape, full vs shrunken).
(b) Now that you have what you think are the most likely
parental genotypes, what are the likely EXPECTED RATIOS from the
parental cross? Based on this ratio, what are the expected
proportions for each type of progeny?
(c) Test your hypothesis with a chi-square test and show your
calculations below. As usual, be sure to clearly state (1) the
calculated chi-square value, (2) the degrees of freedom, (3) the
probability associated with the calculated chi- square value, and
(4) whether you fail to reject or reject the null hypothesis
(written out in a full sentence)