40. Basic Principles of Animal Form & Function 41. Animal Nutrition 42. Circulation & Gas Exchange 43. The Immune System 44. Osmoregulation & Excretion 45. Hormones & the Endocrine System 46. Animal Reproduction 47. Animal Development 48. Neurons, Synapses, & Signaling 49. Nervous Systems 50. Sensory & Motor Mechanisms 51. Animal Behavior