1. Lecture Presentation by Lee Ann Frederick University of Texas at Arlington Chapter 7 The Axial Skeleton © 2015 Pearson Education Inc.

2. An Introduction to the Axial Skeleton Learning Outcomes 7-1 Identify the bones of the axial skeleton, and specify their functions. 7-2 Identify the bones, foramina, and fissures of the cranium and face, and explain the significance of the markings on the individual bones. 7-3 Describe the structure and functions of the orbital complex, nasal complex, and paranasal sinuses. © 2015 Pearson Education Inc.

3. An Introduction to the Axial Skeleton Learning Outcomes 7-4 Describe the key structural differences among the skulls of infants, children, and adults. 7-5 Identify and describe the curvatures of the spinal column, and indicate the function of each. 7-6 Identify the vertebral regions, and describe the distinctive structural and functional characteristics of vertebrae in each region. 7-7 Explain the significance of the articulations between the thoracic vertebrae and the ribs, and between the ribs and sternum. © 2015 Pearson Education Inc.

4. An Introduction to the Axial Skeleton Structures of Bones Articulations Contacts with other bones Landmarks (bone markings; marks) Areas of muscle and ligament attachment Foramina Openings for nerves and blood vessels © 2015 Pearson Education Inc.

5. 7-1 The Axial Skeleton The Axial Skeleton Forms the longitudinal axis of the body Has 80 bones The skull 8 cranial bones 14 facial bones Bones associated with the skull 6 auditory ossicles The hyoid bone © 2015 Pearson Education Inc.

6. 7-1 The Axial Skeleton The Axial Skeleton The vertebral column 24 vertebrae (singular  vertebra) The sacrum The coccyx The thoracic cage 24 ribs The sternum © 2015 Pearson Education Inc.

7. © 2015 Pearson Education, Inc. Figure 7-1a The Axial Skeleton. Cranium (see Figure 8-1) 8 SKELETAL SYSTEM 206 APPENDICULAR SKELETON AXIAL SKELETON 80 Face Auditory ossicles Hyoid Ribs Vertebrae Coccyx 14 1 24 1 1 Sacrum Vertebral column Thoracic cage Skull and associated bones Skull Associated bones 29 25 26 An anterior view of the entire skeleton, with the axial components highlighted. The numbers in the boxes indicate the number of bones in the adult skeleton. a Sternum 1 24 6

8. © 2015 Pearson Education, Inc. Figure 7-1b The Axial Skeleton. Skull Sternum Costal cartilages Cervical vertebrae Thoracic vertebrae Lumbar vertebrae Sacrum b Anterior (left) and posterior (right) views of the axial skeleton. The individual bones associated with the skull are not visible. Coccyx Ribs

9. 7-1 The Axial Skeleton Functions of the Axial Skeleton Supports and protects organs in body cavities 1.Attaches to muscles of head, neck, and trunk 2.Performs respiratory movements 3.Stabilizes parts of appendicular skeleton © 2015 Pearson Education Inc.

10. 7-2 The Skull The Skull Protects: The brain Entrances to respiratory system Entrance to digestive system Contains: 22 bones 8 cranial bones Form the braincase, or cranium 14 facial bones Protect and support entrances to digestive and respiratory tracts © 2015 Pearson Education Inc.

11. © 2015 Pearson Education, Inc. Figure 7-2 Cranial and Facial Subdivisions of the Skull (Part 1 of 3). SKULL FACECRANIUM ASSOCIATED BONES 7 8 2 Maxillae Palatine bones Nasal bones Inferior nasal conchae Zygomatic bones Lacrimal bones Vomer Mandible 2 2 2 2 2 1 1 Ethmoid Occipital bone Parietal bones Frontal bone Temporal bones Sphenoid 14 1 2 1 2 1 1 Hyoid bone 6 Auditory ossicles enclosed in temporal bones (detailed in Chapter 17) 1 7 Hyoid bone

12. © 2015 Pearson Education, Inc. Figure 7-2 Cranial and Facial Subdivisions of the Skull (Part 2 of 3). Nasal bone Lacrimal bone Vomer Zygomatic bone Maxilla Mandible Facial bones protect and support the entrances to the digestive and respiratory tracts. Cranial bones surround and protect the brain. Ethmoid Sphenoid Frontal bone Occipital bone Temporal bone Parietal bone

13. © 2015 Pearson Education, Inc. Figure 7-2 Cranial and Facial Subdivisions of the Skull (Part 3 of 3). Auditory ossicles

14. 7-2 The Skull Cranial Bones Enclose the cranial cavity Which contains the brain And its fluids, blood vessels, nerves, and membranes © 2015 Pearson Education Inc.

15. 7-2 The Skull Facial Bones Superficial facial bones For muscle attachment Deep facial bones Separate the oral and nasal cavities Form the nasal septum © 2015 Pearson Education Inc.

16. © 2015 Pearson Education, Inc. Figure 7-3a The Adult Skull. Parietal bone (left) Parietal bone (right) Sagittal suture Lambdoid suture Squamous suture Temporal bone Mastoid process Styloid process Occipital condyle External occipital protuberance Mandible Major Sutures of the Skull Posterior view a Occipital bone

17. © 2015 Pearson Education, Inc. Figure 7-3b The Adult Skull. Sagittal suture Nasal bones Major Sutures of the Skull Superior view b Lambdoid suture Coronal suture Zygomatic Bone Frontal bone Parietal bone (right) Parietal bone (left) Occipital bone

18. © 2015 Pearson Education, Inc. Figure 7-3c The Adult Skull. Mandible Lateral view c Occipital bone Temporal bone Parietal bone Frontal bone Major Sutures of the Skull Coronal suture Lambdoid suture Squamous part of temporal bone External acoustic meatus Mastoid process Styloid process Zygomatic process of temporal bone Temporal process of zygomatic bone Zygomatic arch Squamous suture Sphenoid Supraorbital foramen Nasal bone Lacrimal bone Ethmoid Infraorbital foramen Maxilla Zygomatic bone Mental foramen Mental protuberance

19. © 2015 Pearson Education, Inc. Figure 7-3d The Adult Skull. Parietal bone Anterior view d Sagittal suture Coronal suture Nasal bone Ethmoid Temporal bone Palatine bone Lacrimal bone Zygomatic bone Mastoid process of temporal bone Middle nasal concha (part of ethmoid) Inferior nasal concha Perpendicular plate of ethmoid Vomer Bony nasal septum Mental protuberance Foramen or Fissure Major Structures Using Passageway Frontal Bone Sphenoid Supraorbital foramen Optic canal Superior orbital fissure Supraorbital nerve (branch of N V) Supraorbital artery Optic nerve (N II) Ophthalmic artery Oculomotor nerve (N III), trochlear nerve (N IV), opthalmic branch of trigeminal nerve (N V), and abducens nerve (N VI) Maxillary branch of trigeminal nerve (N V) Inferior orbital fissure Maxilla Infraorbital foramen Infraorbital nerve, branch of maxillary nerve (N V) Infraorbital artery Mandible Mental foramen Mental nerve, branch of mandibular nerve (N V) Mental vessels

20. © 2015 Pearson Education, Inc. Figure 7-3e The Adult Skull. Inferior view e Frontal bone Maxilla Palatine bone Zygomatic bone Zygomatic arch Medial and lateral pterygoid processes Vomer Styloid process Mandibular fossa Occipital condyle Mastoid process Lambdoid suture Occipital bone External occipital protuberance Sphenoid Foramen lacerum (with temporal and occipital bones) Foramen ovale Temporal Bone External acoustic meatus Carotid canal Stylomastoid foramen Internal carotid artery after leaving carotid canal Auditory tube Mandibular branch of trigeminal nerve (N V) Air in meatus conducts sound to eardrum Internal carotid artery Facial nerve (N V) Occipital Bone Foramen magnum Jugular foramen (with temporal bone) Medulla oblongata (most caudal portion of brain) Accessory nerve (XI) Vertebral arteries Glossopharyngeal, vagus, and accessory nerves (N IX, X, XI)

21. © 2015 Pearson Education, Inc. Figure 7-4 Sectional Anatomy of the Skull (Part 1 of 9).

22. © 2015 Pearson Education, Inc. Figure 7-4 Sectional Anatomy of the Skull (Part 2 of 9).

23. 7-2 The Skull Superficial Facial Bones Maxillae = maxillary bones Lacrimal Nasal Zygomatic Mandible Deep Facial Bones Palatine Inferior nasal conchae Vomer © 2015 Pearson Education Inc.

24. 7-2 The Skull Sinuses Cavities that decrease the weight of the skull 1.Lined with mucous membranes 2.Protect the entrances of the respiratory system © 2015 Pearson Education Inc.

25. 7-2 The Skull Sutures The immovable joints of the skull The four major sutures 1. Lambdoid suture 2. Coronal suture 3. Sagittal suture 4. Squamous suture © 2015 Pearson Education Inc.

26. 7-2 The Skull Lambdoid Suture Separates occipital from parietal bones May contain sutural (Wormian) bones Coronal Suture Attaches frontal bone to parietal bones The calvaria (skullcap) Consists of occipital, parietal, and frontal bones © 2015 Pearson Education Inc.

27. 7-2 The Skull Sagittal Suture Between the parietal bones From lambdoid suture to coronal suture Squamous Sutures Form boundaries between temporal bones and parietal bones © 2015 Pearson Education Inc.

28. 7-2 The Cranial Bones of the Skull The Cranial Bones Occipital bone Parietal bones Frontal bone Temporal bones Sphenoid Ethmoid © 2015 Pearson Education Inc.

29. 7-2 The Cranial Bones of the Skull The Occipital Bone Functions of the occipital bone Forms the posterior and inferior surfaces of the cranium Articulations of the occipital bone Parietal bones Temporal bones Sphenoid First cervical vertebra (atlas) © 2015 Pearson Education Inc.

30. 7-2 The Cranial Bones of the Skull The Occipital Bone Marks of the occipital bone External occipital protuberance External occipital crest Occipital condyles articulate with neck Inferior and superior nuchal lines: attachment sites of muscles and ligaments © 2015 Pearson Education Inc.

31. 7-2 The Cranial Bones of the Skull The Occipital Bone Foramina of the occipital bone Foramen magnum connects cranial and spinal cavities Jugular foramen for jugular vein Hypoglossal canals for hypoglossal nerves © 2015 Pearson Education Inc.

32. © 2015 Pearson Education, Inc. Figure 7-5a The Occipital and Parietal Bones. Hypoglossal canal Occipital condyle Foramen magnum External occipital crest Superior nuchal line Inferior nuchal line External occipital protuberance Occipital bone, inferior view a

33. 7-2 The Cranial Bones of the Skull The Parietal Bones Functions of the parietal bones Form part of the superior and lateral surfaces of the cranium Articulations of the parietal bones Other parietal bone Occipital bone Temporal bone Frontal bone Sphenoid © 2015 Pearson Education Inc.

34. 7-2 The Cranial Bones of the Skull The Parietal Bones Marks of the parietal bones Superior and inferior temporal lines To attach temporalis muscle Grooves for cranial blood vessels © 2015 Pearson Education Inc.

35. © 2015 Pearson Education, Inc. Figure 7-5b The Occipital and Parietal Bones. Superior temporal line Inferior temporal line Right parietal bone, lateral view b

36. 7-2 The Cranial Bones of the Skull The Frontal Bone Functions of the frontal bone Forms the anterior cranium and upper eye sockets Contains frontal sinuses Articulations of the frontal bone Parietal bone Maxillary Metopic suture Ethmoid Lacrimal bone Zygomatic bone Spenoid Nasal bone © 2015 Pearson Education Inc.

37. 7-2 The Cranial Bones of the Skull The Frontal Bone Marks of the frontal bone Frontal squama (forehead) Supraorbital margin (protects eye) Lacrimal fossa (for tear ducts) Frontal sinuses © 2015 Pearson Education Inc.

38. 7-2 The Cranial Bones of the Skull The Frontal Bone Foramina of the frontal bone Supraorbital foramen For blood vessels of eyebrows, eyelids, and frontal sinuses Supraorbital notch An incomplete supraorbital foramen © 2015 Pearson Education Inc.

39. © 2015 Pearson Education, Inc. Figure 7-6a The Frontal Bone. Frons Frontal (metopic) suture Glabella Supraorbital margin Supraorbital notch Anterior surface a Superior temporal line

40. © 2015 Pearson Education, Inc. Figure 7-6b The Frontal Bone. Inferior (orbital) surface b Lacrimal fossa Frontal sinus Supraorbital margin Supraorbital foramen

41. 7-2 The Cranial Bones of the Skull The Temporal Bones Functions of the temporal bones 1.Part of lateral walls of cranium and zygomatic arches 2.Articulate with mandible 3.Surround and protect inner ear 4.Attach muscles of jaws and head © 2015 Pearson Education Inc.

42. 7-2 The Cranial Bones of the Skull The Temporal Bones Articulations of the temporal bones Zygomatic bone Sphenoid Parietal bone Occipital bone Mandible © 2015 Pearson Education Inc.

43. 7-2 The Cranial Bones of the Skull The Temporal Bones Marks of the temporal bones Squamous part Zygomatic process Mandibular fossa Mastoid process Styloid process Petrous part Auditory ossicles © 2015 Pearson Education Inc.

44. 7-2 The Cranial Bones of the Skull Squamous Part Borders the squamous suture Zygomatic Process Inferior to the squamous portion Articulates with temporal process of zygomatic bone Forms zygomatic arch (cheekbone) Mandibular Fossa Articulates with the mandible © 2015 Pearson Education Inc.

45. 7-2 The Cranial Bones of the Skull Mastoid Process For muscle attachment Contains mastoid air cells connected to middle ear Styloid Process To attach tendons and ligaments of the hyoid, tongue, and pharynx Petrous Part Encloses structures of the inner ear © 2015 Pearson Education Inc.

46. 7-2 The Cranial Bones of the Skull Auditory Ossicles Three tiny bones in tympanic cavity (middle ear) Transfer sound from tympanic membrane (eardrum) to inner ear © 2015 Pearson Education Inc.

47. 7-2 The Cranial Bones of the Skull The Temporal Bones Foramina of the temporal bones Carotid canal for internal carotid artery Foramen lacerum For carotid and small arteries Hyaline cartilage Auditory tube © 2015 Pearson Education Inc.

48. 7-2 The Cranial Bones of the Skull The Temporal Bones Foramina of the temporal bones External acoustic meatus (canal) ends at tympanic membrane Stylomastoid foramen for facial nerve Internal acoustic meatus (canal) For blood vessels and nerves of the inner ear Facial nerve © 2015 Pearson Education Inc.

49. © 2015 Pearson Education, Inc. Figure 7-7a The Temporal Bones. Petrous part Medial view of the right temporal bone a Squamous part (cerebral surface) Internal acoustic meatus Zygomatic process Styloid process Mastoid process

50. © 2015 Pearson Education, Inc. Figure 7-7b The Temporal Bones. b Lateral view of the right temporal bone Mastoid process External acoustic meatus Styloid process Zygomatic process Mandibular fossa Squamous part

51. © 2015 Pearson Education, Inc. Figure 7-7bc The Temporal Bones. c A cutaway view of the mastoid cells Mastoid process, cut to show mastoid cells External acoustic meatus b Lateral view of the right temporal bone Mastoid process External acoustic meatus Styloid process Zygomatic process Mandibular fossa Squamous part

52. 7-2 The Cranial Bones of the Skull The Sphenoid Functions of the sphenoid Part of the floor of the cranium Unites cranial and facial bones Strengthens sides of the skull Contains sphenoidal sinuses © 2015 Pearson Education Inc.

53. 7-2 The Cranial Bones of the Skull The Sphenoid Articulations of the sphenoid Ethmoid Frontal bone Occipital bone Parietal bone Temporal bone Palatine bones Zygomatic bones Maxillae Vomer © 2015 Pearson Education Inc.

54. 7-2 The Cranial Bones of the Skull The Sphenoid Marks of the sphenoid Sphenoid body Sella turcica Hypophyseal fossa Sphenoidal sinuses Lesser wings Greater wings Pterygoid processes © 2015 Pearson Education Inc.

55. 7-2 The Cranial Bones of the Skull Sphenoid Body At the central axis of the sphenoid Sella Turcica Saddle-shaped enclosure On the superior surface of the body Hypophyseal Fossa A depression within the sella turcica Holds the pituitary gland © 2015 Pearson Education Inc.

56. 7-2 The Cranial Bones of the Skull Sphenoidal Sinuses On either side of the body Inferior to the sella turcica Lesser Wings Anterior to the sella turcica © 2015 Pearson Education Inc.

57. 7-2 The Cranial Bones of the Skull Greater Wings Form part of the cranial floor Sphenoidal spine Posterior wall of the orbit Pterygoid Processes Form pterygoid plates To attach muscles of the lower jaw and soft palate © 2015 Pearson Education Inc.

58. 7-2 The Cranial Bones of the Skull The Sphenoid Foramina of the sphenoid Optic canals for optic nerves Superior orbital fissure for blood vessels and nerves of the orbit Foramen rotundum for blood vessels and nerves of the face Foramen ovale for blood vessels and nerves of the face Foramen spinosum for blood vessels and nerves of the jaws © 2015 Pearson Education Inc.

59. © 2015 Pearson Education, Inc. Figure 7-8a The Sphenoid. Foramen rotundum Optic groove Optic canal Lesser wing Sphenoidal spine Greater wing Foramen ovale Foramen spinosum Sella turcica Superior surface a

60. © 2015 Pearson Education, Inc. Figure 7-8b The Sphenoid. Superior orbital fissure Sphenoidal sinus Body Lesser wing Orbital surface Greater wing Foramen rotundum Pterygoid plates b Anterior surface Pterygoid process

61. 7-2 The Cranial Bones of the Skull The Ethmoid Functions of the ethmoid Forms anteromedial floor of the cranium Roof of the nasal cavity Part of the nasal septum and medial orbital wall Contains ethmoidal air cells (network of sinuses) © 2015 Pearson Education Inc.

62. 7-2 The Cranial Bones of the Skull The Ethmoid Articulations of the ethmoid Frontal bone Sphenoid Nasal bone Lacrimal bone Palatine bone Maxillary bones Inferior nasal conchae Vomer © 2015 Pearson Education Inc.

63. 7-2 The Cranial Bones of the Skull The Ethmoid Three parts of the ethmoid 1.The cribriform plate 2.The two lateral masses 3.The perpendicular plate © 2015 Pearson Education Inc.

64. 7-2 The Cranial Bones of the Skull The Cribriform Plate Floor of the cranium Roof of the nasal cavity Contains the crista galli The Two Lateral Masses Ethmoidal labyrinth (ethmoidal air cells) Superior nasal conchae Middle nasal conchae The Perpendicular Plate Part of the nasal septum © 2015 Pearson Education Inc.

65. 7-2 The Cranial Bones of the Skull The Ethmoid Foramina of the ethmoid Olfactory foramina In the cribriform plate For olfactory nerves © 2015 Pearson Education Inc.

66. © 2015 Pearson Education, Inc. Figure 7-9a The Ethmoid. Olfactory foramina Cribriform plate Crista galli Lateral mass containing ethmoidal labyrinth Perpendicular plate Superior surface a

67. © 2015 Pearson Education, Inc. Figure 7-9b The Ethmoid. Perpendicular plate Crista galli Superior nasal concha Middle nasal concha Posterior surface b

68. 7-2 The Facial Bones of the Skull The Facial Bones Maxillae (maxillary bones) Palatine bones Nasal bones Vomer Inferior nasal conchae Zygomatic bones Lacrimal bones Mandible © 2015 Pearson Education Inc.

69. 7-2 The Facial Bones of the Skull The Maxillae Functions of the maxillae Support upper teeth Form inferior orbital rim Form lateral margins of external nares Form upper jaw and hard palate Contain maxillary sinuses (largest sinuses) © 2015 Pearson Education Inc.

70. 7-2 The Facial Bones of the Skull The Maxillae Articulations of the maxillae Frontal bones Ethmoid With one another All other facial bones except the mandible © 2015 Pearson Education Inc.

71. 7-2 The Facial Bones of the Skull The Maxillae Marks of the maxillae Orbital rim protects eye and orbit Anterior nasal spine attaches cartilaginous anterior nasal septum Alveolar processes border the mouth and support upper teeth Palatine processes form the hard palate (roof of mouth) Maxillary sinuses lighten bone Nasolacrimal canal protects lacrimal sac and nasolacrimal duct © 2015 Pearson Education Inc.

72. 7-2 The Facial Bones of the Skull The Maxillae Foramina of the maxillae Infraorbital foramen For sensory nerve to brain (via foramen rotundum of sphenoid) Inferior orbital fissure For cranial nerves and blood vessels © 2015 Pearson Education Inc.

73. © 2015 Pearson Education, Inc. Figure 7-10a The Maxillae and Palatine Bones. Orbital rim Infraorbital foramen Anterior nasal spine Alveolar process Zygomatic process An anterolateral view of the right maxilla. a

74. 7-2 The Facial Bones of the Skull The Palatine Bones Functions of the palatine bones Form the posterior portion of the hard palate Contribute to the floors of the orbits © 2015 Pearson Education Inc.

75. 7-2 The Facial Bones of the Skull The Palatine Bones Articulations of the palatine bones With other palatine bone Maxillae Sphenoid Ethmoid Inferior nasal conchae Vomer © 2015 Pearson Education Inc.

76. 7-2 The Facial Bones of the Skull The Palatine Bones Divisions of the palatine bones Horizontal plate: posterior part of hard palate Perpendicular plate from horizontal plate to orbital process of orbit floor Foramina of the palatine bones Many in the lateral portion of the horizontal plate For small blood vessels and nerves of the roof of the mouth © 2015 Pearson Education Inc.

77. © 2015 Pearson Education, Inc. Figure 7-10b The Maxillae and Palatine Bones. b Palatine bone (horizontal plate) Palatine process Alveolar process Maxillary sinus Superior view of a horizontal section through right maxilla and palatine bone; note the size and orientation of the maxillary sinus.

78. © 2015 Pearson Education, Inc. Figure 7-10c The Maxillae and Palatine Bones. An anterior view of the two palatine bones. c Orbital process Perpendicular plate Horizontal plate

79. 7-2 The Facial Bones of the Skull The Nasal Bones Functions of the nasal bones Support the bridge of the nose Connect to cartilages of the distal part of the nose (external nares) © 2015 Pearson Education Inc.

80. 7-2 The Facial Bones of the Skull The Nasal Bones Articulations of the nasal bones With other nasal bones Ethmoid Frontal bones Maxillae © 2015 Pearson Education Inc.

81. 7-2 The Facial Bones of the Skull The Vomer Functions of the vomer Forms the inferior portion of the bony nasal septum Articulations of the vomer Sphenoid Ethmoid Palatine bones Maxillae Cartilaginous part of the nasal septum © 2015 Pearson Education Inc.

82. 7-2 The Facial Bones of the Skull The Inferior Nasal Conchae Functions of the inferior nasal conchae To create air turbulence in the nasal cavity To increase the epithelial surface area To warm and humidify inhaled air © 2015 Pearson Education Inc.

83. 7-2 The Facial Bones of the Skull The Inferior Nasal Conchae Articulations of the inferior nasal conchae Ethmoid Maxillae Palatine bones Lacrimal bones © 2015 Pearson Education Inc.

84. 7-2 The Facial Bones of the Skull The Zygomatic Bones Functions of the zygomatic bones Contribute to the rim and lateral wall of the orbit Form part of the zygomatic arch Articulations of the zygomatic bones Sphenoid Frontal bone Temporal bones Maxillae © 2015 Pearson Education Inc.

85. 7-2 The Facial Bones of the Skull The Zygomatic Bones Marks of the zygomatic bones Temporal process Meets the zygomatic process of the temporal bone Foramina of the zygomatic bones Zygomaticofacial foramen For sensory nerves of cheeks © 2015 Pearson Education Inc.

86. 7-2 The Facial Bones of the Skull The Lacrimal Bones Functions of the lacrimal bones The smallest facial bones Form part of the medial wall of the orbit Articulations of the lacrimal bones Frontal bone Maxillae Ethmoid © 2015 Pearson Education Inc.

87. 7-2 The Facial Bones of the Skull The Lacrimal Bones Marks of the lacrimal bones Lacrimal sulcus Location of the lacrimal sac Leads to the nasolacrimal canal (between orbit and nasal cavity) © 2015 Pearson Education Inc.

88. © 2015 Pearson Education, Inc. Figure 7-11 The Smaller Bones of the Face (Part 1 of 2). Supraorbital foramen Nasal bone Sphenoid Temporal bone Zygomaticofacial foramen Zygomatic bone Infraorbital foramen Maxilla Bony nasal septum Perpendicular plate of ethmoid Vomer

89. © 2015 Pearson Education, Inc. Figure 7-11 The Smaller Bones of the Face (Part 2 of 2). Lacrimal sulcus Bony nasal septum Perpendicular plate of ethmoid Optic canal Superior orbital fissure Lacrimal bone Middle nasal concha Inferior nasal concha Temporal process of zygomatic bone Mastoid process Vomer

90. 7-2 The Facial Bones of the Skull The Mandible Functions of the mandible Forms the lower jaw Articulations of the mandible Mandibular fossae of the temporal bones © 2015 Pearson Education Inc.

91. 7-2 The Facial Bones of the Skull The Mandible Marks of the mandible Body of the mandible is horizontal portion Alveolar processes support the lower teeth Mental protuberance attaches facial muscles A depression on the medial surface for submandibular salivary gland Mylohyoid line for insertion of the mylohyoid muscle (floor of mouth) © 2015 Pearson Education Inc.

92. 7-2 The Facial Bones of the Skull The Mandible Marks of the mandible Ramus ascending from the mandibular angle on either side Condylar process articulates with temporal bone at temporomandibular joint Coronoid process: insertion point for temporalis muscle (closes the jaws) Mandibular notch separates condylar and coronoid processes © 2015 Pearson Education Inc.

93. 7-2 The Facial Bones of the Skull The Mandible Foramina of the mandible Mental foramina For sensory nerves of lips and chin Mandibular foramen Entrance to the mandibular canal For blood vessels and nerves of lower teeth © 2015 Pearson Education Inc.

94. 7-2 The Facial Bones of the Skull The Hyoid Bone Functions of the hyoid bone Supports the larynx Attaches muscles of the larynx, pharynx, and tongue Articulations of the hyoid bone Connects lesser horns to styloid processes of temporal bones © 2015 Pearson Education Inc.

95. 7-2 The Facial Bones of the Skull The Hyoid Bone Marks of the hyoid bone Body of the hyoid Attaches muscles of larynx, tongue, and pharynx © 2015 Pearson Education Inc.

96. 7-2 The Facial Bones of the Skull The Hyoid Bone Marks of the hyoid bone Greater horns (greater cornua) Support larynx Attach muscles of the tongue Lesser horns (lesser cornua) Attach stylohyoid ligaments Support hyoid and larynx © 2015 Pearson Education Inc.

97. © 2015 Pearson Education, Inc. Figure 7-12a The Mandible. Head Articular surface for temporomandibular joint Mandibular notch Ramus Condylar process Body Angle Coronoid process Teeth Mental protuberance Mental foramen A lateral and slightly superior view of the mandible a

98. © 2015 Pearson Education, Inc. Figure 7-12b The Mandible. Articular surface Condylar process Coronoid process Mandibular foramen Mylohyoid line Depression for submandibular salivary gland Alveolar process A medial view of the right mandible b

99. © 2015 Pearson Education, Inc. Figure 7-13 An Anterior View of the Hyoid Bone. Greater horn Lesser horn Body An anterior view of the hyoid bone

100. 7-3 The Orbital and Nasal Complexes The Eye Sockets (Orbits) Frontal bone (roof) Maxilla (floor) Maxillary, lacrimal, and ethmoid bones (orbital rim and medial wall) Sphenoid and palatine bones © 2015 Pearson Education Inc.

101. © 2015 Pearson Education, Inc. Figure 7-14 The Orbital Complex (Part 1 of 2). Frontal bone Sphenoid Superior orbital fissure Interior orbital fissure Zygomatic bone Infraorbital groove Infraorbital foramen Maxilla Supraorbital notch Optic canal Ethmoid Lacrimal bone Lacrimal sulcus Nasolacrimal canal Palatine bone

102. © 2015 Pearson Education, Inc. Figure 7-14 The Orbital Complex (Part 2 of 2). Sphenoid Optic canal Superior orbital fissure Ethmoid Nasolacrimal canal Frontal bone Inferior orbital fissure Infraorbital groove Zygomatic bone Maxilla Infraorbital foramen Supraorbital notch

103. 7-3 The Orbital and Nasal Complexes Bones of the Nasal Cavities and Paranasal Sinuses Make Up the Nasal Complex Frontal bone, sphenoid, and ethmoid Superior wall of nasal cavities Maxillae, lacrimal bones, ethmoid, and inferior nasal conchae Lateral walls of nasal cavities Maxillae and nasal bones Bridge of nose © 2015 Pearson Education Inc.

104. © 2015 Pearson Education, Inc. Figure 7-15a The Nasal Complex. Frontal sinus Ethmoid air cells Sphenoidal sinus Maxillary sinus Locations of the paranasal sinuses. a

105. © 2015 Pearson Education, Inc. Figure 7-15b The Nasal Complex. Frontal bone Frontal sinuses Ethmoid Nasal bone Palatine bone (bony palate) Maxilla (bony palate) Sphenoidal sinuses Sphenoid Superior Middle Inferior nasal concha Nasal conchae of ethmoid A sagittal section through the skull, with the nasal septum removed to show major features of the wall of the right nasal cavity. The frontal and sphenoidal sinuses are visible. b

106. 7-3 The Orbital and Nasal Complexes Paranasal Sinuses Air-filled chambers connected to the nasal cavities Lighten skull bones Provide mucous epithelium (flushes nasal cavities) © 2015 Pearson Education Inc.

107. 7-4 Fontanelles The Infant Skull Grows rapidly Is large compared to the body Has many ossification centers © 2015 Pearson Education Inc.

108. 7-4 Fontanelles The Infant Skull Fusion is not complete at birth Two frontal bones Four occipital bones Several sphenoidal and temporal elements © 2015 Pearson Education Inc.

109. 7-4 Fontanelles Fontanelles Are areas of fibrous connective tissue (soft spots) Cover unfused sutures in the infant skull Allow the skull to flex during birth © 2015 Pearson Education Inc.

110. 7-4 Fontanelles Anterior Fontanelle Frontal, sagittal, and coronal sutures Occipital Fontanelle Lambdoid and sagittal sutures Sphenoidal Fontanelles Squamous and coronal sutures Mastoid Fontanelles Squamous and lambdoid sutures © 2015 Pearson Education Inc.

111. © 2015 Pearson Education, Inc. Figure 7-16a The Skull of an Infant. Coronal suture Frontal bone Parietal bone Greater wing of sphenoid Nasal bone Maxilla MandibleTemporal bone Squamous suture Occipital bone Lambdoid suture Lateral view Sphenoidal fontanelle Mastoid fontanelle Fontanelles a

112. © 2015 Pearson Education, Inc. Figure 7-16b The Skull of an Infant. Coronal suture Fontanelles Anterior fontanelle Posterior fontanelle Occipital bone Lambdoid suture Superior view Parietal bone Coronal suture Parietal bone b Frontal bone Frontal suture Sagittal suture

113. 7-5 The Vertebral Column The Vertebral Column (Spine) Protects the spinal cord Supports the head and body 26 bones 24 vertebrae, the sacrum, and the coccyx © 2015 Pearson Education Inc.

114. © 2015 Pearson Education, Inc. Figure 7-17 The Vertebral Column. Primary curves develop before birth, and secondary curves after birth. Spinal Curves The cervical curve, a secondary curve, develops as the infant learns to balance the weight of the head on the vertebrae of the neck. The thoracic curve, a primary curve, accommo- dates the thoracic organs. The lumbar curve, a secondary curve, balances the weight of the trunk over the lower limbs; it develops with the ability to stand. The sacral curve, a primary curve, accommodates the abdominopelvic organs. Thoracic (12 vertebrae) Lumbar (5 vertebrae) Sacral Coccygeal Cervical (7 vertebrae) Vertebral Regions Regions are defined by anatomical characteristics of individual vertebrae. C1C1 C2C2 C3C3 C4C4 C5C5 C6C6 C7C7 T1T1 T2T2 T3T3 T4T4 T5T5 T6T6 T7T7 T8T8 T9T9 T 10 T 11 T 12 L2L2 L3L3 L4L4 L5L5 L1L1

115. 7-5 The Vertebral Column Vertebrae The neck Seven cervical vertebrae The upper back 12 thoracic vertebrae Each articulates with one or more pair of ribs The lower back Five lumbar vertebrae © 2015 Pearson Education Inc.

116. 7-5 The Vertebral Column The Sacrum and Coccyx The fifth lumbar vertebra articulates with the sacrum The sacrum articulates with the coccyx © 2015 Pearson Education Inc.

117. 7-5 The Vertebral Column Four Spinal Curves 1. Cervical curve 2. Thoracic curve 3. Lumbar curve 4. Sacral curve © 2015 Pearson Education Inc.

118. 7-5 The Vertebral Column Thoracic and Sacral Curves Are called primary curves (present during fetal development) Or accommodation curves (accommodate internal organs) Lumbar and Cervical Curves Are called secondary curves (appear after birth) Or compensation curves (shift body weight for upright posture) © 2015 Pearson Education Inc.

119. © 2015 Pearson Education, Inc. Clinical Note 7-2a Kyphosis, Lordosis, and Scoliosis. Kyphosis a

120. © 2015 Pearson Education, Inc. Clinical Note 7-2b Kyphosis, Lordosis, and Scoliosis. Lordosis b

121. © 2015 Pearson Education, Inc. Clinical Note 7-2c Kyphosis, Lordosis, and Scoliosis. Scoliosis c

122. 7-5 The Vertebral Column Vertebral Anatomy The vertebral body (centrum) Transfers weight along the spine The vertebral arch Posterior margin of vertebral foramen The articular processes Lateral projections between laminae and pedicles © 2015 Pearson Education Inc.

123. © 2015 Pearson Education, Inc. Figure 7-18a Vertebral Anatomy. a Vertebral body The major components of a typical vertebra Pedicle Articular processes Vertebral arch

124. 7-5 The Vertebral Column Vertebral Anatomy The vertebral arch Pedicles Walls of the vertebral arch Laminae Roof of the vertebral arch © 2015 Pearson Education Inc.

125. 7-5 The Vertebral Column Vertebral Anatomy The vertebral arch Spinous process Projection where vertebral laminae fuse Transverse process Projection where laminae join pedicles © 2015 Pearson Education Inc.

126. 7-5 The Vertebral Column Vertebral Anatomy The articular processes Superior articular process Inferior articular process Have articular facets on articular faces © 2015 Pearson Education Inc.

127. © 2015 Pearson Education, Inc. Figure 7-18b Vertebral Anatomy. A lateral and slightly inferior view of a vertebra Inferior articular process Inferior articular facet Spinous process Vertebral body Superior articular process Transverse process Pedicle Arrow passing through vertebral foramen b

128. © 2015 Pearson Education, Inc. Figure 7-18c Vertebral Anatomy. Spinous process Inferior articular process Superior articular process Transverse process Inferior articular facet Pedicle An inferior view of a vertebra Vertebral foramen Vertebral body c

129. 7-5 The Vertebral Column Vertebral Foramina Intervertebral foramina Gaps between pedicles of adjacent vertebrae For nerve connections to spinal cord Vertebral canal Formed by vertebral foramina Encloses the spinal cord © 2015 Pearson Education Inc.

130. 7-5 The Vertebral Column Intervertebral Discs Are pads of fibrocartilage Separate the vertebral bodies Absorb shocks © 2015 Pearson Education Inc.

131. © 2015 Pearson Education, Inc. Figure 7-18d Vertebral Anatomy. Superior articular facets Superior articular process Lamina of vertebral arch Spinous process Intervertebral disc Transverse process Vertebral body Inferior articular process A posterior view of three articulated vertebrae d

132. © 2015 Pearson Education, Inc. Figure 7-18e Vertebral Anatomy. Inferior articular facet Arrow passing through vertebral canal Vertebral body A lateral and sectional view of three articulated vertebrae Superior articular facets Lamina of vertebral arch Spinous process Transverse process Intervertebral foramen Intervertebral disc e

133. 7-6 Vertebral Regions Vertebral Regions Vertebrae are numbered By region, from top (superior) to bottom (inferior) C 1 articulates with skull, L 5 with sacrum Vertebrae of each region Have characteristics determined by functions © 2015 Pearson Education Inc.

134. 7-6 Vertebral Regions Regions of the Vertebral Column Cervical (C) Thoracic (T) Lumbar (L) Sacral (S) Coccygeal (Co) © 2015 Pearson Education Inc.

135. 7-6 Vertebral Regions The Cervical Vertebrae Small body (support only head) Large vertebral foramen (largest part of spinal cord) Concave superior surface Slope posterior to anterior C 1 (atlas) has no spinous process All others have short spinous processes Tip of each spinous process is notched (bifid) © 2015 Pearson Education Inc.

136. © 2015 Pearson Education, Inc. Figure 7-19a The Cervical Vertebrae. Spinous process of vertebra prominens C1C1 C2C2 C3C3 C4C4 C5C5 C6C6 C7C7 A lateral view of the cervical vertebrae, C 1 –C 7. a

137. © 2015 Pearson Education, Inc. Figure 7-19b The Cervical Vertebrae. b A superior view of a representative cervical vertebra showing characteristics of C 3 –C 6. Notice the typical features listed in Table 7–1. Vertebral body Vertebral arch Vertebral foramen Pedicle Transverse process Costal process Spinous process Lamina Superior articular process Superior articular facet Transverse foramen

138. © 2015 Pearson Education, Inc. Figure 7-19c The Cervical Vertebrae. Transverse process Inferior articular process A lateral view of the same vertebra as in b. Superior articular process Spinous process Bifid tip of spinous process Inferior articular facet Location of transverse foramen Vertebral body c

139. 7-6 Vertebral Regions The Cervical Vertebrae Transverse processes Are fused to costal processes Which encircle transverse foramina (protect arteries and veins) Atlas (C 1 ) Articulates with occipital condyles of skull Has no body or spinous process Has a large, round foramen within anterior and posterior arches © 2015 Pearson Education Inc.

140. 7-6 Vertebral Regions The Cervical Vertebrae Axis (C 2 ) Supports the atlas Has heavy spinous process To attach muscles of head and neck Axis and atlas bodies fuse during development to form the dens © 2015 Pearson Education Inc.

141. © 2015 Pearson Education, Inc. Figure 7-19d The Cervical Vertebrae. d The atlas (C 1 ) and axis (C 2 ) in posterolateral view. Anterior arch Transverse ligament Dens of axis Atlas (C 1 ) Axis (C 2 ) Posterior arch

142. 7-6 Vertebral Regions The Cervical Vertebrae Vertebra prominens (C 7 ) Transitions to thoracic vertebrae Has a long spinous process with a broad tubercle Has large transverse processes Ligamentum nuchae (elastic ligament) extends from C 7 to skull © 2015 Pearson Education Inc.

143. 7-6 Vertebral Regions Thoracic Vertebrae (T 1 –T 12 ) Have heart-shaped bodies Larger bodies than in C 1 –C 7 Smaller vertebral foramen than in C 1 –C 7 Long, slender spinous processes Dorsolateral surfaces of body have costal facets Which articulate with heads of ribs © 2015 Pearson Education Inc.

144. 7-6 Vertebral Regions Thoracic Vertebrae (T 1 –T 12 ) T 1 –T 10 Have transverse costal facets On thick transverse processes for rib articulation Ribs at T 1 –T 10 Contact costal and transverse costal facets T 1 –T 8 articulate with two pairs of ribs At superior and inferior costal facets T 9 –T 11 articulate with one pair of ribs T 10 –T 12 transition to lumbar vertebrae © 2015 Pearson Education Inc.

145. © 2015 Pearson Education, Inc. Figure 7-20a The Thoracic Vertebrae. a A lateral view of the thoracic region of the vertebral column. The vertebra prominens (C 7 ) resembles T 1, but lacks facets for rib articulation. Vertebra T 12 resembles the first lumbar vertebra (L 1 ) but has a fact for rib articulation. Vertebra prominens Intervertebral foramen Thoracic vertebrae (T 1 –T 12 ) T4T4 T3T3 T2T2 T1T1 C7C7 T5T5 T6T6 T7T7 T8T8 T9T9 T 10 T 11 T 12 L1L1

146. © 2015 Pearson Education, Inc. Figure 7-20b The Thoracic Vertebrae. b Thoracic vertebra, superior view. Vertebral body Superior costal facet Transverse costal facet Transverse process Lamina Superior articular facet Vertebral foramen Spinous process

147. © 2015 Pearson Education, Inc. Figure 7-20c The Thoracic Vertebrae. Thoracic vertebra, lateral view. Transverse costal facet for tubercle of superior rib Transverse process Spinous process Superior costal facet for head of superior rib Vertebral body Inferior costal facet for head of inferior rib c

148. 7-6 Vertebral Regions Lumbar Vertebrae (L 1 –L 5 ) Largest vertebrae Oval-shaped bodies Thicker bodies than T 1 –T 12 No costal or transverse costal facets Triangular vertebral foramen Superior articular processes Face up and in Inferior articular processes Face down and out © 2015 Pearson Education Inc.

149. 7-6 Vertebral Regions Lumbar Vertebrae (L 1 –L 5 ) Transverse processes Slender Project dorsolaterally Spinous processes Short, heavy For attachment of lower back muscles © 2015 Pearson Education Inc.

150. © 2015 Pearson Education, Inc. Figure 7-21a The Lumbar Vertebrae. Sacrum Coccyx A lateral view of the lumbar vertebrae, sacrum, and coccyx a L1L1 L2L2 L3L3 L4L4 L5L5

151. © 2015 Pearson Education, Inc. Figure 7-21b The Lumbar Vertebrae. A lateral view of a typical lumbar vertebra Superior articular process Transverse process Pedicle Vertebral body Spinous process Inferior articular process Inferior articular facet b

152. © 2015 Pearson Education, Inc. Figure 7-21c The Lumbar Vertebrae. A superior view of the same vertebra shown in part b Superior articular process Transverse process Pedicle Vertebral body Vertebral foramen Spinous process Transverse process Superior articular facet Lamina c

153. © 2015 Pearson Education, Inc. Table 7-1 Regional Differences in Vertebral Structure and Function (Part 1 of 2).

154. © 2015 Pearson Education, Inc. Table 7-1 Regional Differences in Vertebral Structure and Function (Part 2 of 2).

155. 7-6 Vertebral Regions The Sacrum Is curved, more in males than in females Protects reproductive, urinary, and digestive organs Attaches: The axial skeleton to pelvic girdle of appendicular skeleton Broad muscles that move the thigh © 2015 Pearson Education Inc.

156. 7-6 Vertebral Regions The Sacrum The adult sacrum Consists of five fused sacral vertebrae Fuses between puberty and ages 25–30 Leaving transverse lines Sacral canal Replaces the vertebral canal © 2015 Pearson Education Inc.

157. 7-6 Vertebral Regions The Sacrum Sacral cornua Horn shaped Formed by laminae of the fifth sacral vertebra Which do not meet at midline Sacral hiatus Opening at the inferior end of the sacral canal Formed by ridges of sacral cornua Covered by connective tissues © 2015 Pearson Education Inc.

158. 7-6 Vertebral Regions The Sacrum Median sacral crest Fused spinous processes Four pairs of sacral foramina open to either side Lateral sacral crest Fused transverse processes Attach to muscles of lower back and hip © 2015 Pearson Education Inc.

159. 7-6 Vertebral Regions The Sacrum Auricular surface Thick, flattened area Articulates with pelvic girdle (forming sacroiliac joint) Sacral tuberosity Rough area Attaches ligaments of the sacroiliac joint © 2015 Pearson Education Inc.

160. 7-6 Vertebral Regions The Sacrum Base The broad superior surface Ala Wings at either side of the base To attach muscles Sacral promontory At the center of the base Apex The narrow inferior portion Articulates with the coccyx © 2015 Pearson Education Inc.

161. 7-6 Vertebral Regions The Coccyx Attaches ligaments and a constricting muscle of the anus Mature coccyx Consists of three to five fused coccygeal vertebrae First two coccygeal vertebrae Have transverse processes Have unfused vertebral arches Coccygeal cornua Formed by laminae of first coccygeal vertebra © 2015 Pearson Education Inc.

162. © 2015 Pearson Education, Inc. Figure 7-22a The Sacrum and Coccyx. Articular process Entrance to sacral canal Lateral sacral crest Median sacral crest Sacral cornu Coccygeal cornu Sacral tuberosity Sacral hiatus A posterior view a

163. © 2015 Pearson Education, Inc. Figure 7-22b The Sacrum and Coccyx. Lateral sacral crest Median sacral crest Sacral cornu Coccygeal cornu Sacral curve A lateral view from the right side Sacral promontory Auricular surface b Coccyx

164. © 2015 Pearson Education, Inc. Figure 7-22c The Sacrum and Coccyx. Coccyx An anterior view Sacral promontory Base Ala Transverse lines Apex Sacral foramina c

165. 7-7 The Thoracic Cage The Thoracic Cage The skeleton of the chest Supports the thoracic cavity Consists of: Thoracic vertebrae Ribs Sternum (breastbone) The Rib Cage Formed of ribs and sternum © 2015 Pearson Education Inc.

166. © 2015 Pearson Education, Inc. Figure 7-23a The Thoracic Cage. Jugular notch T1T1 Clavicular articulation Sternum Manubrium Body Xiphoid process Costal cartilages Vertebrochondral ribs (ribs 8–10) Floating ribs (ribs 11–12) True ribs (ribs 1–7) False ribs (ribs 8–12) 1 2 3 4 5 6 7 8 9 10 11 12 T 11 T 12 An anterior view, showing the costal cartilages and the sternum a

167. © 2015 Pearson Education, Inc. Figure 7-23b The Thoracic Cage. True ribs (ribs 1–7) False ribs (ribs 8–12) A posterior view, showing the articulations of the ribs and vertebrae 1 2 3 4 5 6 7 8 9 11 12 10 C7C7 T1T1 T3T3 T4T4 T5T5 T2T2 T6T6 T7T7 T8T8 T9T9 T 10 T 11 T 12 L1L1 1 2 3 4 5 6 7 8 9 11 12 10 b

168. 7-7 The Thoracic Cage Functions of the Thoracic Cage 1.Protects organs of the thoracic cavity Heart, lungs, and thymus 2.Attaches muscles 1.For respiration 2.Of the vertebral column 3.Of the pectoral girdle and the upper limbs © 2015 Pearson Education Inc.

169. 7-7 The Thoracic Cage Ribs (Costae) Are 12 pairs of long, curved, flat bones Extending from the thoracic vertebrae Ribs are divided into two types 1. True ribs 2. False ribs © 2015 Pearson Education Inc.

170. 7-7 The Thoracic Cage Ribs 1–7 (True Ribs) Vertebrosternal ribs Connected to the sternum by costal cartilages © 2015 Pearson Education Inc.

171. 7-7 The Thoracic Cage Ribs 8–12 (False Ribs) Do not attach directly to the sternum Vertebrochondral ribs (ribs 8–10) Fuse together Merge with cartilage before reaching the sternum Floating or vertebral ribs (ribs 11–12) Connect only to the vertebrae and back muscles Have no connection with the sternum © 2015 Pearson Education Inc.

172. 7-7 The Thoracic Cage Structures of the Ribs The head (capitulum) At the vertebral end of the rib Has superior and inferior articular facets The neck The short area between the head and the tubercle © 2015 Pearson Education Inc.

173. 7-7 The Thoracic Cage Structures of the Ribs The tubercle (tuberculum) A small dorsal elevation Has an auricular facet that contacts the facet of its thoracic vertebra (at T 1 –T 10 only) The tubular body (shaft) Attaches muscles of the pectoral girdle and trunk Attaches to the intercostal muscles that move the ribs © 2015 Pearson Education Inc.

174. © 2015 Pearson Education, Inc. Figure 7-24a The Ribs. Transverse costal facet Demifacet Tubercle of rib Angle Neck Head (capitulum) Vertebral end A superior view of the details of rib structure and the articulations between the ribs and thoracic vertebrae a

175. © 2015 Pearson Education, Inc. Figure 7-24b The Ribs. A posterior view of the head of a representative rib from the right side (ribs 2–9) Attachment to costal cartilage (sternal end) Head Neck Angle Costal groove Body Tubercle Articular facets b

176. 7-7 The Thoracic Cage The Sternum A flat bone In the midline of the thoracic wall Three parts of the sternum 1.The manubrium 2.The sternal body 3.The xiphoid process © 2015 Pearson Education Inc.

177. 7-7 The Thoracic Cage Manubrium The superior portion of sternum Broad, triangular shape Articulates with clavicles (collarbones) Articulates with cartilages of first rib pair Has a jugular notch, a shallow indentation between clavicular articulations © 2015 Pearson Education Inc.

178. 7-7 The Thoracic Cage The Sternal Body Is tongue-shaped Attaches to the manubrium Attaches to costal cartilages of ribs 2–7 The Xiphoid Process Is the smallest part of the sternum Attaches to the sternal body Attaches to diaphragm and rectus abdominis muscles © 2015 Pearson Education Inc.

179. 7-7 The Thoracic Cage Development of the Sternum The developing sternal body Consists of four unfused bones Completes fusion about age 25 Leaving transverse lines The xiphoid process Is the last part of sternum to fuse Can easily be broken away © 2015 Pearson Education Inc.