Question 1 Color-blindness is a sex-linked recessive trait. A woman who is a carrier for the trait has two boys with a colorblind man. What is the probability that both boys are color-blind? A. 0% B. 25% C. 50% D. 100%

Question 2 A human male may inherit all of the following EXCEPT: A. his mother's mother's X chromosome. B. his mother's father's X chromosome. C. his father's father's Y chromosome. D. his father's mother's X chromosome.

Question 3 If the traits that Mendel had studied had not followed the Law of Independent Assortment, how might Mendel's findings have changed? A. Alleles for the same trait would not have separated independently of each other. B. Alleles for different traits would not have separated independently of each other. C. Homologous chromosomes would exhibit alleles coding for different traits at the same loci. D. Phenotypes of a single trait would resemble both parental phenotypes on the same individual.

Question # 4 Which of the following explains why a cross between“ plant with green pea pods and a plant with yellow pea pods results in offspring of plants with either yellow or green pea pods, and does not result in plants with yellowish green pea pods? A. the Law of Segregation B. the Law of Independent Assortment C. the Hardy-Weinberg Principle D. pleiotropic separation

Question # 5 A dihybrid cross is made between individuals with the genotype BbFf. What is the ratio of the following genotypes BBFF, BBff, bbFF, bbff in the progeny? (see next slide for sample dihybrid cross) A. 9,3,3, 1 B. 4,3,2,1 C. 1, 3, 3, 1 D. 1, 1, 1, 1

Question # 6 DNA replication occurs during: A. prophase. B. metaphase. C. telophase. D. interphase

Question # 7 A primary spermatocyte is (see Reproductive Lecture): A. haploid and contains 23 chromosomes. B. haploid and contains 46 chromosomes. C. diploid and contains 23 chromosomes. D. diploid and contains 46 chromosomes.

Question # 8 Radiation therapy is used to treat some forms of cancer by damaging DNA and thus killing the rapidly reproducing cancerous cells. Why might radiation treatment have a greater effect on cancer cells than normal cells? A. Normal cells have more time between S phases to repair damaged DNA. B. Damaged DNA is more reactive to radiation. C. Cancer cells have lost the ability to repair damaged DNA. D. The effect of radiation is the same, but there are more cancer cells than normal cells.

Question # 9 During mitosis, the nuclear envelope of a mammalian cell: A. disintegrates during replication of the chromosomes. B. disintegrates while crossing over is taking place. C. disintegrates while the chromosomes condense. D. remains intact.

Question # 10 A change in the amount of chromosome or a change in the structure of the chromosome or DNA of an organism is called A. Natural selection B. Mutation C. Genetic drift D. Chromosome condensation E. None of the above

Question # 11 Which of the following side-effects might be experienced by a patient who is administered a dose of thyroxine? A. An increase in endogenous TSH production B. A decrease in endogenous TSH production C. An increase in endogenous thyroxine production D. A decrease in endogenous parathyroid hormone production

Question # 12 As a young girl, Maria suffered a head injury that damaged her pituitary. An injury to the pituitary is particularly serious because of all the functions controlled by this gland. As Maria got older, she and her doctors found that all of the following EXCEPT her __________ were affected: A. blood sugar level B. Metabolic rate C. growth D. menstrual cycle E. water regulation

Question # 13 What is the role of a second messenger in hormone action? A. it relays a hormone’s message inside a target cell B. it informs a gland as to whether its hormones are having an effect C. it stops hormone action when it is no longer needed D. it signals a cell to secrete a hormone E. all of the listed responses are correct

Question # 14 Which, if any, of the following statements is true? A. Diploid cells can divide by mitosis B. Diploid cells can divide by meiosis C. Haploid cells can divide by mitosis D. Haploid cells cannot divide by meiosis E. All of the above responses are correct.

Question # 15 Pea plants are tall if they have a genotype TT or Tt, and they are short if they have genotype tt. A tall plant is mated with a short plant. Which outcome below would indicate that the tall parent plant was heterozygous? A. The ratio of tall offspring to short offspring is 1:1 B. All of the offspring are tall C. There is not enough information to answer question D. The ratio of tall offspring to short offspring is 3:1 E. All of the offspring are short. * Do the Punnett square using TT x tt and Tt x tt

Question 16 Physically, what are different alleles? A. different alleles are different DNA sequences found at the same locus on sister chromatids B. Different alleles are different phenotypes for a particular character C. Different alleles are different particles found in gametes D. Different alleles are different DNA sequence found at the same locus on homologous chromosomes

Question 17 In the pedigree diagram below, the darkened figures indicate an individual with hemophilia. a sex-linked recessive disease. The genotype of the female marked A is: (contd…next slide)

A. X H X h B. X H X H C. X h X h D. X h Y