45. Sexual reproduction
(A)only occurs in vertebrates.
(B)allows more offspring to be produced per individual.
(C) allows a parent to pass on 100% of their genes to offspring.
(D)increases genetic variation.

41. Diving mammals like whales and seals experience frequent periods when they are not able to breathe air. Which of the following is a muscle adaptation they show to this challenge? (A)increased capillary densities (B)increased myoglobin concentrations (C) increased amounts of sarcoplasmic reticulum (D)increased expression of acetylcholine receptors

42. Consider a tadpole becoming a toad. You would expect to find it changing its form of nitrogenous waste from ______ to______. (A)ammonia, urea(B)urea, ammonia(C)urea, uric acid(D)uric acid, urea(E)uric acid, ammonia

43. All of the following are functions of the mammalian kidney except (A)water retention(B)filtration of blood(C)excretion of nitrogenous waste(D)regulation of salt balance in the blood (E)production of urea

44. Which of the following has both endocrine and exocrine activity? (A)the pituitary gland(B)parathyroid glands(C)salivary glands(D)the pancreas(E)adrenal glands

46. Sickle-cell anemia is a human disease that occurs as a result of what type of mutation in the β-globin gene? (A)silent(B)missense(C)nonsense(D)frameshift

47. Which of the following represents the proper order of events in embryonic development? (A)fertilization, cleavage, gastrulation, organogenesis, neurulation (B)fertilization, cleavage, gastrulation, neurulation, organogenesis (C) fertilization, gastrulation, neurulation, cleavage, organogenesis (D)fertilization, gastrulation, cleavage, neurulation, organogenesis (E)fertilization, gastrulation, cleavage, organogenesis, neurulation

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

49. A doctor discovers that her patient can produce antibodies against some bacterial pathogens, but he is unable to protect himself against viral infections. The doctor suspects a disorder in her patient's (A)B cells(B)plasma cells(C)cytotoxic T cells(D)suppressor T cells(E)macrophages

50. The proximate causes of behavior are interactions with the environment, but behavior is ultimately shaped by (A)hormones(B)evolution(C)sexuality(D)pheromones

1. Look at the picture. The boy in long pants is the only one who is_____. (A) f ishing (B) holding a basket (C) sitting (D) wearing a cap