28. In a ___ distribution, many sample plots will contain few or no individuals while other plots will contain a large number.
(A) clumped
(B) regular
(C) random
(D) uniform
(E) none of the above

24. The immediate, direct effect of auxin in cell elongation, according to the acid growth hypothesis, is to (A) increase the hydrostatic pressure in cells, stretching their walls. (B) activate ATP-driven proton (H+) pumps, and result in an accumulation of H+ in cytoplasm. (C) shift the pH and thus activate enzymes that break the hydrogen bonds. (D) move water into vacuoles. (E) activate the synthesis of new cytoplasm.

25. A precursor in the synthesis of the peptidoglycan of bacterial cell walls is UDP-: (A) galactose. (B) glucose.(C) glucuronic acid. (D) N-acetylglucosamine. (E) penicillin. 

26. ___ ecologists would study the distribution of Taiwania cryptomerioidesin mountain areas of Taiwan. (A) Population (B) Community (C) Ecosystem (D) Behavioral (E) Landscape

27. Which of the following best describes directional selection? (A) Two or more phenotypes are common and drive diversity. (B) It occurs when one extreme phenotype has an advantage over all other phenotypes. (C) Larger individuals in a population have higher rates of survival than average and small individuals. (D) All of the above. (E) B and C are correct.

29. Groups of plant or animal subpopulations which are spatially isolated but exchange individuals is called a (A) metapopulation. (B) community. (C) clumped distribution. (D) corridor. (E) none of the above.

30. Which of the following situations dose NOT increase species diversity in a community? (A) predation by keystone species. (B) habitat heterogeneity. (C) competitive exclusion. (D) moderate disturbances. (E) immigration of species.

31. Which ofthe following is an example ofMiillerian mimicry? (A) Two species of unpalatable butterfly that have the same color pattern. (B) A day-flying hawkmoth that looks like a wasp. (C) A katydid whose wings look like a dead leaf. (D) Two species of rattlesnake that both rattle their tails. (E) Two species of moths with wing spots that look like owl's eyes.

32. Which of the following is NOT a shared characteristic of all chordates? (A) dorsal, hollow nerve cord. (B) notochord. (C) post-anal tail.(D) pharyngeal slits. (E) four-chambered heart.

3 3. Natural selection is based on all of the following except (A) inheritance of acquired characteristics. (B) the fittest individuals leave the most offspring. (C) variation exists within populations. (D) populations tend to produce more individuals than the environment can support. (E) differential reproductive success within populations.

34. In which specific way does the founder effect lead to changes in gene frequency? (A) Small populations get large and then small again. (B) By chance alone, the descendants are not genetically representative of the ancestral population. (C) Involves homozygous ancestral populations that become heterozygous. (D) Natural selection acts as a principal cause of change in the process. (E) Depends on the importance of nonneutral mutations.