Astudent analyzed ears of corn that demonstrated two traits in the f2 kernels, purple or white colors and smooth or wrinkled shapes. a tabulation of 135 individual kernels gave the following results: purple and smooth = 75 white and smooth = 28 purple and wrinkled = 24 white and wrinkled = 8 what would be the only phenotype present in the f1 generation?

It is known that the in dihybrid cross (a cross between two different traits), the phenotypic ratio between the offspring of two heterozygous parents in the F2 generation is 9:3:3:1.

purple and smooth = 75                (≈ 9 · 8)

white and smooth = 28                  (≈ 3 · 8)

purple and wrinkled = 24               (= 3 · 8)

white and wrinkled = 8                   (= 1 · 8)

So, the ratio between the offspring is close to 9:3:3:1 in F2 generation.

This means, that the only heterozygotes are present in the F1 generation, and they must be purple and smooth.

explanation:

the fossil record extends back to a dog-like ancestor some 55 million years ago, which gave rise to the first horse-like species 55 to 42 million years ago in the genus eohippus.

1. the geologists have established a set of principals that can can be used o determine the relative ages of rock. this principal is applied to sedimentary and volcanic rocks. the rocks exposed to wall of grand canyon has layers and by studying the number of horizontal layers in the rock(strata) the relative age can be determined. the layer first formed will appear at the bottom and the the layer of strata last formed appear at the top. by using this information the approximate age of rocks can be determined.

2. carbon dating is used to find the relative age of rock in numbers which means for the rocks that has age between 1-70,000 years.

3. for the rocks of age range between 1,000 - billion of years potassium-argon dating is used.