1 Alternate forms of a gene that influence the same characteristic and are found at the same location in homologous chromosomes are calledA) alleles. B) phenotypes. C) genotypes. D) prototypes. E) paratypes. 2 Which is a characteristic of alleles?A) They occur in pairs on homologous chromosomes. B) They separate when forming gametes. C) They reoccur in pairs at fertilization. D) They can be exactly the same or represent alternate phenotypes. E) All of the choices are correct. 3 In humans, brown eyes are dominant over blue eyes. A brown-eyed woman who has a blue-eyed child has the genotypeA) bb. B) Bb. C) BB. D) None of these above represent her genotype. E) Not able to determine from the information given. 4 The albinistic trait is recessive. If an albino woman is married to a man with normal coloring and they have an albino child, what is the genotype of the man?A) homozygous B) heterozygous C) sex-linked D) male E) female 5 If 25% of the offspring of one set of parents show the recessive phenotype, the parents were probablyA) both homozygous recessive. B) both homozygous dominant. C) both heterozygous. D) one homozygous dominant, one homozygous recessive. E) You would never expect this percentage of a phenotype given any known mode of inheritance. 6 Amniocentesis reveals that an embryo has Tay-Sachs disease. What are the genotypes of the parents if they appear normal (t = Tay-Sachs; Tay-Sachs is a recessive disease)?A) Tt x Tt B) TT x TT C) tt x tt D) Tt x tt E) None of the choices are correct. 7 The inheritance of blood types in humans can be explained byA) epistasis. B) linked genes. C) simple dominance. D) multiple alleles. E) polygenic inheritance. 8 If one parent has type B blood and the other has type AB, what type might the child have?A) A or O only B) B or O only C) A or B only D) A, B, AB only E) A, B, O, or AB 9 What would be the result if Mendel had chosen an organism that was incapable of self-fertilizing?A) He could not have observed segregation of traits. B) He would have to create F1 heterozygotes from two different sets of parents prior to the crosses. C) He would not have been able to observe flower traits. D) The pods would not have contained different types of seeds. E) True-breeding plants could not have been created. 10 In a certain pea plant, round and green seeds are dominant to wrinkled and yellow seeds. These two traits assort independently. A dihybrid cross is performed between two parents heterozygous for both traits. 2345 progeny were obtained in the F1 generation. How many do you expect to be of the same phenotype as the parents plants?A) 147 B) 439 C) 1319 D) 721 E) It is impossible to determine from these data. 11 After performing a testcross, one of the progeny demonstrates the dominant trait. Which of the following is NOT true of that progeny?A) It will be a heterozygote. B) It will be true-breeding. C) It will have a recessive allele. D) It will resemble one of the parents. E) None of the above is necessarily false. 12 You are attempting to create a true-breeding variety of hamster which has dark pigments at the tips of the ears, face, and limbs. However, you're having a hard time establishing reproducible results during the hot summer months. Your conclusion is thatA) the gene for your trait must be involved in an epistatic relationship with another. B) the trait is influenced through a polygenic mechanism. C) environmental effects are influencing the activity of the allele's protein. D) codominance of several genes cause disproportionate lethality in the desired offspring which die in the heat. E) the parental lines are not true-breeding. 13 Which of these is NOT a reason Mendel was able to use pea plants as an experimental system to study inheritance?A) Mendel knew that he could expect to observe segregation of traits among the offspring. B) Both the male and female sexual organs are enclosed within each pea flower. C) Pea plants are small and easy to grow, and they have a relatively short generation time. D) A large number of pure varieties of peas were available. E) Self-fertilization will not take in this model plant. 14 A 1:2:1 ratio describes the genotype which arises from a monohybrid cross of two heterozygous individuals.A) True B) False 15 Two genes are involved in the same biochemical pathway and are investigated using a dihybrid cross. They interact in such a way that one (gene A) interferes with the expression of the other (gene B). We call this phenomenonA) continuous variation B) incomplete dominance C) codominance D) epistasis E) polygenic