Homozygous recessive individuals show the dominant phenotype. True False

The observable traits expressed by an organism are described as its _______. a. phenotype b. genotype c. alleles d. zygote

Analysis of X-Linked Dominant and Recessive Traits A young boy is color-blind. His one brother and five sisters are not. The boy has three maternal uncles and four maternal aunts. None of his uncles children or grandchildren is color-blind. One of the maternal aunts married a color-blind man, and half of her children, both male and female, are color-blind. The other aunts married men who have normal color vision. All their daughters have normal vision, but half of their sons are color-blind. a. Which of the boys four grandparents transmitted the gene for color blindness? b. Are any of the boys aunts or uncles color-blind? c. Is either of the boys parents color-blind?

Refer to question 4. Assuming complete dominance, the F2 generation will show a phenotypic ratio of _______. a.3:1 b.9:1 c. 1:2:1 d. 9:3:3:1

A walnut comb rooster is mated to three hens. Hen A, which has a walnut comb, has offspring in the ratio of 3 walnut to 1 rose. Hen B, which has a pea comb, has offspring in the ratio of 3 walnut to 3 pea to 1 rose to 1 single. Hen C, which has a walnut comb, has only walnut comb offspring. What are the genotypes of the rooster and the three hens?

Analysis of Autosomal Recessive and Dominant Traits Describe the phenotype and primary gene or protein defect of the X-linked recessive disease muscular dystrophy.

Analysis of X-Linked Dominant and Recessive Traits The following is a pedigree for a common genetic trait. Analyze the pedigree to determine whether the trait is inherited as: a. autosomal dominant b. autosomal recessive c. X-linked dominant d. X-linked recessive e. Y-linked

Analysis of Autosomal Recessive and Dominant Traits Huntington disease is a rare, fatal disease that usually develops in the fourth or fifth decade of life. It is caused by a single autosomal dominant allele. A phenotypically normal man in his twenties who has a 2-year-old son of his own learns that his father has developed Huntington disease. What is the probability that he himself will develop the disease? What is the chance that his young son will eventually develop the disease?

Redgreen color blindness is an X-linked recessive disorder in humans. Your friend is the daughter of a color-blind father. Her mother had normal color vision, but her maternal grandfather was color-blind. What is the probability that your friend is color-blind? (a) 1 (b) (c) (d) (e) 0

A recessive trait will be observed in individuals that are ________ for that trait. a. heterozygous b. homozygous or heterozygous c. homozygous d. diploid