42. Which event of fertilization occurs first?
(A) fast block to polyspermy
(B) the entry of sperm DNA into the egg
(C) the slow block to polyspermy
(D) the acrosomal reaction
(E) the cortical reaction

38. Which of these gland-hormone pairs is mismatched? (A) pancreas-insulin (B) anterior pituitary-growth hormone (C) thyroid-thyroid hormone (D) adrenal-parathyroid hormone (E) ovaries-progesterone

39. Which of these hormone-effect pairs is mismatched? (A) growth hormone-linear growth (B) glucagon-blood pressure (C) aldosterone-blood osmolality (D) thyroid hormone-metabolism (E) glucagon-glucose regulation

40. What cell is haploid? (A) oogonium (B) zygote (C) primary oocyte (D) ovum (E) spermatogonium

41. Which of the choices lists the three phases of the ovarian cycle in the correct order? (A) follicular, luteal, ovulation (B) follicular, proliferative, secretory (C) luteal, ovulation, secretory (D) follicular, ovulation, luteal (E) luteal, secretory, ovulation

43. Which of the following is TRUE of a morphogen? It is a signaling molecule that (A) is required for cell-to-cell contact within the embryo. (B) induces the differentiation of cells within the embryo. (C) induces blastulation of the developing embryo. (D) induces implantation of the embryo into the uterus of mammals. (E) that separates out cytoplasmic factors to their respective cells within the developing embryo.

44. Vaccinations are effective in combating future infections because they induce the production of (A) helper T cells. (B) neutrophils. (C) prostaglandins. (D) mutations in the host genome. (E) memory cells.

45. All of the following are components of nonspecific immunity EXCEPT (A) skin. (B) phagocytes. (C)complement. (D) lysozyme. (E) B cells.

46. Which of the following is true of T cells and B cells? (A) They are effector cells against specific pathogens. (B) They are produced from stem cells of the bone marrow. (C) They can help attack and destroy invading pathogens. (D) They typically have a short life span. (E) All of these statements are true.

47. In the Hardy-Weinberg equation , the genotype frequency of heterozygotes is represented by (A) p2 (B) 2pq (C) q2 (D)p2+q2 (E) p2 + 2pq

48. What mechanism leads to changes in allele frequencies due to random chance? (A) Genetic drift (B) Natural selection (C) Sexual selection (D) Neutral variation (E) inbreeding