In a family where both parents are heterozygous for a recessive genetic disorder (genotype Aa), what is the probability that, when a couple has two children, both children will be affected by the disorder?

In a population of cats, the allele for long tails (L) is dominant over the allele for short tails (l). If the frequency of the long tail allele (L) is 0.7 and the population is in Hardy-Weinberg equilibrium, what is the expected frequency of cats with long tails?

In a population of butterflies, the allele frequency of A is 0.7 and the allele frequency of a is 0.3. According to Hardy-Weinberg equilibrium, what is the expected frequency of the heterozygous genotype (Aa) in this population?

In a population where the allele frequencies of C and c are 0.7 and 0.3 respectively, what is the expected frequency of the cc genotype under Hardy-Weinberg equilibrium?

In a population of wildflowers where the frequency of the red allele c_r is p = 0.7, what is the expected frequency of homozygous red individuals (c_r c_r) under Hardy-Weinberg equilibrium?

In cats, orange coat color is determined by the b allele, and black coat color is determined by the B allele. The heterozygous condition results in a coat pattern known as tortoiseshell. These genes are X-linked. What kinds of offspring would be expected from a cross of a black male and a tortoiseshell female? What are the chances of getting a tortoiseshell male?

In pigs, coat color may be sandy, red, or white. A geneticist spent several years mating true-breeding pigs of all different color combinations, even obtaining true-breeding lines from different parts of the country. For crosses 1 and 4 in the following table, she encountered a major problem: her computer crashed and she lost the data. She nevertheless persevered and, using the limited data shown here, was able to predict the mode of inheritance and the number of genes involved, as well as to assign genotypes to each coat color. Attempt to duplicate her analysis, based on the available data generated from the crosses shown.

When you have formulated a hypothesis to explain the mode of inheritance and assigned genotypes to the respective coat colors, predict the outcomes of the generations where the data were lost.

In another cross, the frog geneticist from Problem 18 mated two purple, utterers with the results shown here. What were the genotypes of the parents? <IMAGE>

In cattle, coats may be solid white, solid black, or black-and-white spotted. When true-breeding solid whites are mated with true-breeding solid blacks, the generation consists of all solid white individuals. After many matings, the following ratio was observed in the generation:

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Explain the mode of inheritance governing coat color by determining how many gene pairs are involved and which genotypes yield which phenotypes. Is it possible to isolate a true-breeding strain of black-and-white spotted cattle? If so, what genotype would they have? If not, explain why not.