In assessing data that fell into two phenotypic classes, a geneticist observed values of 250:150. She decided to perform a x² analysis by using the following two different null hypotheses: (a) the data fit a 3:1 ratio, and (b) the data fit a 1:1 ratio. Calculate the x² values for each hypothesis. What can be concluded about each hypothesis?

In cats, tortoiseshell coat color appears in females. A tortoiseshell coat has patches of dark brown fur and patches of orange fur that each in total cover about half the body but have a unique pattern in each female. Male cats can be either dark brown or orange, but a male cat with tortoiseshell coat is rarely produced. Two sample crosses between males and females from pure-breeding lines produced the tortoiseshell females shown.

Cross I          P: dark brown male × orange female
                      F₁: orange males and tortoiseshell females
Cross II         P: orange male × dark brown female
                      F₁: dark brown males and tortoiseshell females

Why are tortoiseshell cats female?

In cats, tortoiseshell coat color appears in females. A tortoiseshell coat has patches of dark brown fur and patches of orange fur that each in total cover about half the body but have a unique pattern in each female. Male cats can be either dark brown or orange, but a male cat with tortoiseshell coat is rarely produced. Two sample crosses between males and females from pure-breeding lines produced the tortoiseshell females shown.

Cross I          P: dark brown male × orange female
                      F₁: orange males and tortoiseshell females
Cross II         P: orange male × dark brown female
                      F₁: dark brown males and tortoiseshell females

Explain the inheritance of dark brown, orange, and tortoiseshell coat colors in cats.

The seeds in bush bean pods are each the product of an independent fertilization event. Green seed color is dominant to white seed color in bush beans. If a heterozygous plant with green seeds self-fertilizes, what is the probability that 6 seeds in a single pod of the progeny plant will consist of

at least 1 white seed?

The seeds in bush bean pods are each the product of an independent fertilization event. Green seed color is dominant to white seed color in bush beans. If a heterozygous plant with green seeds self-fertilizes, what is the probability that 6 seeds in a single pod of the progeny plant will consist of

all green seeds?

The seeds in bush bean pods are each the product of an independent fertilization event. Green seed color is dominant to white seed color in bush beans. If a heterozygous plant with green seeds self-fertilizes, what is the probability that 6 seeds in a single pod of the progeny plant will consist of

3 green and 3 white seeds?

Blue moon beans produce beans that are either the dominant color blue or the recessive color white. The bean pods for this species always contain four seeds each. If two heterozygous plants that each have the Bb genotype are crossed, what are the predicted frequencies of each of the five outcome classes for combinations of blue and white seeds in pods?