42. The seeds of many plant species are dispersed by a harmless temporary attachment to an animal's fur or feathers. This form of dispersal can be classified as
(A)ectoparasitism.
(B)amensalism.
(C)mutualism.
(D) pollination.
(E) phoresy.

38. Place the events of parturition in the correct order. (1) Stretch-sensitive neurons send signals to the hypothalamus. (2) Oxytocin receptors increase in the uterus. (3) Prostaglandin levels increase. (4) Estradiol levels increase. (5) Oxytocin levels increase. (6) Uterine muscles start to contract. (A)1,2,4,5,3,6 (B)4,2,1,5,6,3 (C)5,2,4,1,3,6 (D) 1,6,4,2,5,3 (E) 4,3,1,2,5,6

39. Antigen-presenting cells include (A)macrophages. (B)macrophages and B cells. (C)dendritic cells and macrophages. (D) dendritic cells and B cells. (E) macrophages, B cells and dendritic cells.

40. Several butterfly species that are edible to birds have very similar color patterns to the generally inedible monarch butterfly. This is best described as an example of what? (A)Batesian mimicry (B)Müllerian mimicry (C)Crypsis (D) Intimidation (E) aposematic coloration

41. Which of the following germ layer-structure is mismatched? (A)mesoderm-notochord (B)endoderm-lungs or respiratory tube (C)ectoderm-epidermis (D) mesoderm-digestive tract (E) ectoderm-brain

43. Which of these types of islands is predicted to have the lowest number of species? (A)small island near mainland (B)large island near mainland (C)large island far from mainland (D) small island far from mainland (E) the island closest to mainland regardless of size

44. Primary production is generally highest in (A)tundra. (B)desert. (C)wetlands. (D) tropical rain forests. (E) tropical oceans.

45. DNA methylation (A)increases transcription. (B)inhibits transcription. (C)increases crossover events. (D) decreases crossover events. (E) promotes post-translational modification of proteins.

46. These are the only vertebrates in which blood flows directly from respiratory organs to body tissues without first returning to the heart. (A)Amphibians (B)Birds (C)Fishes (D) Mammals (E) Reptiles

47. The clonal selection theory is an explanation for (A)how a single type of stem cell can produce both red blood cells and white blood cells. (B)how antibody proteins can be molded to fit antigens after the antigen interacts with the antibody-producing type of cell. (C)how an antigen can induce the multiplication of B cells to result in production of high levels of specific antibodies. (D) how HIV can disrupt the immune system. (E) how macrophages can recognize specific T cells and B cells. 

48. ________ is a water-soluble hormone derived from the nervous system that regulates blood volume and blood pressure? (A)Antidiuretic hormone (B)Aldosterone (C)Cortisol (D) Oxytocin (E) Adrenocorticotropic hormone