Exam 9: Inheritance

Human ABO blood groups are determined by three alleles: IA, IB and i. A man with blood group AB has a number of children by a woman with blood group A. Their first child has blood group B. What is the probability that the second child will also have blood group B?

Which of the following statements in relation to individuals carrying the AB blood group is CORRECT?

Which of the following statements about Gregor Mendel is INCORRECT?

In a testcross involving tomatoes, one tomato plant has the genotype O/o ; R/r. The genotype of the other plant is

In tomatoes, the alleles for a gene controlling fruit shape assort independently of the alleles of a gene controlling fruit colour. Round-shaped fruit are dominant to oval-shaped fruit and red fruit are dominant to yellow fruit. A homozygous, red, round-fruit tomato plant is crossed to a tomato plant with yellow oval fruit to produce an F₁ generation. The F₁ plants are crossed to pure-breeding red oval plants. The phenotypic ratio for the offspring of this second cross would be expected to be

A geneticist is studying various phenotypic traits in the toes of rats that are controlled by a mixture of both recessive and dominant alleles. He decides to cross some of his subjects with a new mutant strain that carries a dominant trait for no toes. The progeny of this cross would be an example of

Polydactyly (extra fingers or toes) in humans is inherited as an autosomal dominant trait. Some heterozygotes, however, do not have any visible abnormality. This situation could result from

Linkage is

The distance between genes on a genetic map is calculated using

The presence or absence of hair on the mid-digital region of a finger is determined by a single autosomal gene. The presence of hair is dominant to the absence of hair. In the pedigree below, shading represents the presence of mid-digital hair. If the parents have a 5th child, what is the probability that it will have mid-digital hair?

The vinegar fly, Drosophila melanogaster, has a gene that controls the shape of the wings. The wild-type phenotype is flat wings, but a mutation in the gene produces curled wings. You would expect

Imprinting is

Epistasis is

Alternative forms (alleles) of a gene separate into gametes after meiosis with equal probability. This is known as

The flowers of snapdragons are red, pink or white. Crossing homozygous red snapdragons with homozygous white snapdragons produces offspring that have pink flowers. Which of the following crosses would produce the highest percentage of white flowers?

A gene that controls coat colour in cattle has 2 alleles; C^R (red) and C^W (white). The heterozygotes have a roan colour. If roan cattle are crossed to white cattle, which of the following phenotypic ratios would be expected in the offspring?

In mice, a gene controlling coat colour has 2 alleles; B (black) and b (white). A pure breeding black mouse is crossed to a white mouse and all the offspring are black. The offspring are then crossed to white mice. The phenotypes of the offspring of this second cross are expected to be

The position of a gene on a chromosome is known as the

In dogs, length of hair is controlled by a gene with 2 alleles. Short hair is dominant to long hair. Two heterozygous short-haired dogs are crossed and they produce a short-haired puppy. What is the probability that the puppy is heterozygous?

In tomatoes, the alleles for a gene controlling fruit shape assort independently of the alleles of a gene controlling fruit colour. Round-shaped fruit are dominant to oval-shaped fruit and red fruit are dominant to yellow fruit. A homozygous, red, round-fruit tomato plant is crossed to a tomato plant with yellow oval fruit to produce an F₁ generation. F₁ plants were crossed to plants that were homozygous red and heterozygous round. You would expect the offspring to be