11. Which of the following provides an example of mechanical isolation as a prezygotic barrier?
(A) two species live in different habitats
(B) two species mate at different times
(C) two species share courtship activities
(D) two snails have shells that spiral in different directions

7. Which of the following statements describes a characteristic feature of metaphase? (A) alignment of chromosomes on the equator of the cell (B) separation of the centromeres (C) cytokinesis (D) separation of sister chromatids

8. How many unique gametes could be produced through independent assortment by an individual with the genotype AaBbCCDdEE? (A) 4 (B) 8 (C) 16 (D) 64

9. Use the following information to answer the question. In the figure, the letters A-G represent individual species that all descended from a common ancestor. Which of the following groups of these species forms a monophyletic group? (A) A, B, C, D (B) C and D (C) D, E, and F (D) E, F, and G

10. Cystic fibrosis is a genetic disorder in humans where the person has two homozygous recessive alleles for the gene. If the disease is left untreated, it causes severe health problems in the individual. If 4 in 10,000 newborn babies have the disease, what are the expected frequencies of the dominant (A1) and recessive (A2) alleles according to the Hardy-Weinberg equation? (A) f(A1) = 0.9998, f(A2) = 0.0002 (B) f(A1) = 0.9800, f(A2) = 0.0200 (C) f(A1) = 0.9700, f(A2) = 0.0300 (D) f(A1) = 0.9604, f(A2) = 0.0392

12. Which of the following statements accurately describes the lysogenic cycle of lambda (λ) phage? (A) The viral genes immediately turn the host cell into a lambda-producing factory. Then the host lyses. (B) The product of one prophage gene is made and it activates most of the other prophage genes. (C) The phage genome is integrated into the host chromosome where it is passed on to daughter cells through binary fission. (D) The phage DNA is copied and accumulates in the cytoplasm. Then a trigger causes capsid proteins to be made and phages are assembled.

13. Which of the following statements correctly describes the colonization of terrestrial habitats by plants? (A) It occurred in conjunction with insects that pollinated them. (B) It occurred in conjunction with fungi that helped provide them with nutrients from the soil. (C) It helped them to escape abundant herbivores in the oceans. (D) It occurred only about 150 million years ago.

14. Which of the following functions is an advantage of seeds compared to spores? (A) using wind as a dispersal agent (B) containing a nutrient store for a developing sporophyte (C) relying on animals for pollination (D) providing nutrition for animals

15. In a field of corn or lettuce on a farm, plants are cultivated with uniform spacing that will maximize plant growth. In natural habitats, however, a uniform pattern of dispersion is much less common. While exceptions do exist, for example in populations of creosote bush in the desert, which of the following best explains why natural populations of plants usually exhibit clumped or random dispersion patterns? (A) Patterns of higher soil moisture, the concentration of soil nutrients, and the distribution of seeds from parent plants may be highly variable. (B) Precipitation across landscapes, especially mountain ranges, is uniform. (C) The competitive interactions between individuals of the same population usually lead to such dispersion patterns. (D) Since nearly all plants are wind-pollinated, the direction of breezes can affect whether plants will produce seeds.

1. Which energy-producing process is thought to have come first during cellular evolution? (A) Photosynthesis (B) Glycolysis (C) Oxidative phosphorylation (D) Proteolysis (E) All of the above originated at the same time.

2. The interaction of the light and heavy chains to form the immunoglobulin molecule is an example of ______ structure. (A) primary (B) secondary (C) tertiary (D) quaternary (E) domain