A scientist is studying traits in corn. The picture shows the traits she is studying. The scientists does a dihybrid cross of two corn plants. One corn plant is homozygous for yellow kernels and heterozygous for smooth kernels. The other corn plant is heterozygous for purple kernels and homozygous for smooth kernels. Which best describes the possible offspring of this cross? a There is a 50% chance of having purple, smooth kernels and a 50% chance of having yellow, smooth kernels. b There is a 50% chance of having purple, wrinkled kernels and a 50% chance of having yellow, shrunken kernels. c There is a 100% chance of having purple, smooth kernels. d There is a 100% chance of having yellow, shrunken kernels.
The correct answer is a) There is a 50% chance of having purple, smooth kernels and a 50% chance of having yellow, smooth kernels.
This is because the cross involves two traits: kernel color and kernel texture. The first corn plant is homozygous for yellow kernels, so all its offspring will have yellow kernels. The first corn plant is heterozygous for smooth kernels, meaning it has one dominant allele for smooth texture and one recessive allele for wrinkled texture. The second corn plant is heterozygous for purple kernels, meaning it has one dominant allele for purple color and one recessive allele for yellow color. Both corn plants are homozygous for smooth kernels, meaning they have two dominant alleles for smooth texture.
When these two corn plants are crossed, the possible combinations of alleles in the offspring are:
1. Yellow Color (YY) x Purple Color (YP):
- 50% chance of YY (yellow kernels)
- 50% chance of YP (yellow kernels)
2. Smooth Texture (SS) x Smooth Texture (SS):
- 100% chance of SS (smooth kernels)
Therefore, there is a 50% chance of having purple, smooth kernels and a 50% chance of having yellow, smooth kernels.