1. Anatomy Chapter 7

2. axis- center consists of the center bones of the body 80 bones 3 major regions: skull vertebral column thoracic cage

4. most complex structure mostly flat bones has about 85 named openings 22 bones, usu interlocked along suture lines 8 cranium bones 14 facial bones

5. helmet encloses and protects the brain, provides areas for muscle attachment for head movements and chewing held together by sutures- immovable joints

6. 8 bones

7. 1. frontal- forehead 2. parietal- largest part (2) 3. occipital- external occipital protuberance foramen magnum occipital condyles 4. temporal (2)- Latin- temporum- time passing external auditory meatus mastoid process styloid process- (stake-like) zygomatic process

10. 5. sphenoid- (spheno-wedge) helps form base of cranium, sides of skull, floors and sides of orbits; keystone sella turcica- Turk’s saddle 6. ethmoid bone- forms most of bony area of nasal cavity & eye orbits cribiform plates crista galli- cock’s comb

12. 14 bones- 13 immovable; 1 movable Fxn: form basic shape of face, provide attachment for muscles, contain cavities for special sense organs, provide openings for air & food, & secure teeth

13. keystone bone of the face form upper jaw, roof of mouth, floors of orbits and nasal cavity

15. form cheekbones

16. horseshoe shaped body

17. fxn: warm and humidify air lighten skull enhance resonance of voice sinus infections

18. aka soft spot allows for movement through birth canal close up by 2 years of age

19. ~ 28” long in adults 26 irregular bones adults infants 33 bones separated by intervertebral discs

20. C1 – atlas nod yes; up and down m’ment C2- axis shake no; side to side m’ment 7 vertebrae

21. Larger than cervical Articulate with ribs 12 vertebrae

22. biggest vertebrae bears most of body’s weight small of back 5 vertebrae

23. sacrum- 5 fused vertebrae form base of column coccyx- lowest part of column 4 fused bones

24. includes ribs, thoracic vetebrae, sternum, costal cartilages fxn: support pectoral girdle, protect viscera, aid in breathing

25. 12 pairs (usually) join to a thoracic vertebra 1 st 7 ribs are TRUE RIBS- join sternum directly by their costal cartilages next 5 pairs are FALSE RIBS- cartilage doesn’t reach sternum directly next 2 (3) pairs are FLOATING RIBS- no cartilaginous attachment to sternum

27. usu break at greatest curvature middle ribs commonly fractured

28. aka breastbone ~ 6” long xyphoid process doesn’t completely ossify until about 40 years old

29. Only bone in body that doesn’t articulate w/ other bones Enables us to talk

33. process of bone developing bones form by replacing existing connective tissue in either of 2 ways: 1. intramembranous ossification- formation of bone directly on or within fibrous membranes

34. simplest, most direct type of bone development osteoblasts form bone tissue skull & clavicles formed this way

35. replacement of hyaline cartilage shapes by bone tissue endo= withinchondro= cartilage

36. growth takes place at the epiphyseal plates on the long bones

37. most bones of body form this way more complex method by age 25 all bones are ossified clavicle- last bone to stop growing bone REMODELING occurs continuously thru-out life

38. Skull: mastoid process, size of skull, forehead, weight Limbs

39. Pelvic cavity: wider in females, pubic arch > 90 o

40. aka articulation bind parts of skeletal system make bone growth possible allow parts of skeleton to change shape during childbirth enable body to move during muscle contraction 230 joints in body

41. 3 classifications: immovable slightly movable freely movable

42. basically NO movement bones lie in close contact w/ each other ex: sutures in skull

43. hyaline cartilage connects bones slightly movable

44. freely movable synovial fluid reduces friction joint capsule menisci- bursae 6 types

45. wider range of motion hip shoulder

46. condyle fits into elliptical cavity variety of m’ments in different planes; rotational m’ment not allowed

47. most joints in wrists & ankles allow sliding & twisting motion

48. cylindrical bone rotates rotation around central axis

49. allows for flexion and extension

50. variety of m’ment