1.  Organs – bones, joints, cartilage, ligaments

2. A. A. Support – hard framework that supports and anchors all soft organs of the body – Ex. Legs act as pillars to support trunk, rib cage supports thorax wall B. B. Protection – skull protects brain, ribs protect heart/lungs, zygomatic arch protect the eye C. C. Movement – skeletal muscles, attached to bone by tendons, used the bones as levers to move the body and it’s parts; arrangement of bones and the design of joints determine the types of movement possible

3. D. D. Storage  Fat stored in the internal cavities  Bone matrix stores minerals (Ca + 2) – “deposits” and “withdrawals” of minerals to and from bones goes on almost continuously E. E. Blood cell formation (hemopoiesis)  Carried on in red bone marrow; hemopoietic tissue – Fig. 6-5  Hemopoietic tissue is found in the ends of long bones  Transformed to yellow bone marrow, an inactive fatty tissue, as person ages

4. A. Classified according to shape B. Contain different proportions of 1. Compact bone (smooth & homogeneous) 2. Spongy (cancellous) bone – spaces & trabeculae (beams)

5. C. Long bones 1. Longer than they are wide 2. Consists of a shaft plus two ends 3. Primarily compact bone; but may contain substantial amounts of spongy bone

6. D. Short bones 1. Roughly cube-like – ex. Wrist/ankle 2. Mostly spongy bone; compact bone only provides a thin surface

7. E. Flat Bone 1. Thin, flattened and usually a bit curved – sternum, ribs, most skull bones 2. Two roughly parallel compact bone surfaces with a layer of spongy bone between

9. F. Irregular bones – some skull, hip, vertebrae 1. Fit none of the preceding classes 2. Complex shapes 3. Mainly spongy bone enclosed by thin layers of compact bone G. Sesamoid bones –a special type of short bone embedded within a tendon; ex. - patella

11. A. Gross Anatomy – What you can see with the naked eye - Fig. 6-1 B. Microscopic Anatomy – Fig. 6-2, 6.3

12. Long Bone – most have the same basic structure 1. diaphysis (shaft) – hollow tube of hard compact bone 2. medullary cavity – hollow area; contains yellow bone marrow 3. epiphyses – bone end or extremities; usually more expanded than diaphysis; thin layer of compact bone forms exterior; interior spongy bone filled with red bone marrow 4. epiphyseal line/plate – remnant of cartilage present at junction of diaphysis & epiphyses in young bones; growth are that allows bones to lengthen 5. articular cartilage – found where long bones articulate (join); cushions the bone ends and absorbs stress during joint movement 6. periosteum – outer surface of diaphysis; richly supplied with nerve fivbers, lymphatic vessels, and blood vessels which enter via nutrient canals 7. endosteum – fibrous membrane that lines medullary cavity

14. Compact bone – Fig. 6-2, 6-3 1. Haversian system – structural unit; circular 7 tubelike; composed of calcified matrix arranged in multiple layers (one inside the other – like an onion) 2. osteocytes (bone cells) – regulate the removal of calcium from bone matrix Osteocyte (within lacuna)

15. Spongy bone 1. Trabeculae – structural unit 2. Osteocytes – only a few cell layers thick; no Haversian system 3. Nutrients reach osteocytes by diffusion

16. Cartilage – Fig. 6-4 1. Fibers embedded in gel (not calcified matrix) 2. Chondrocytes (cartilage cells) 3. Cartilage contains no blood vessels; nutrients diffuse through matrix 4. Function a. supports & reinforces b. cushioning properties c. resists compressive stress (articular cartilage)

18. A. Intramembranous ossification – flat bones form from fibrous membrane – ex. Skull, clavicle, ribs B. Endochondral ossification – bone formation from hyaline cartilage structures; most bones form this way; osteoblasts – bone forming cells osteoclasts – bone reabsorbing cells

19. Cartilage model is the starting point

20. Formation of a bone collar around the shaft of the hyaline cartilage model

21. Cartilage matrix calcifies; chondrocytes die

22. Invasion of internal cavities by periosteal bud and spongy bone formation (3 mo. embryo)

23. As the primary ossification enlarges, osteoclasts break down spongy bone & form medullary cavity

25. Bone growth continues during infancy & youth - long bones lengthen at epiphyseal plate - long bones thicken by a process called appositional growth (inside breaks down at a slower rate than exterior builds up) - some facial bones (nose, mandible) grow throughout life

27. Axial skeleton – forms long axis of body & includes the bones of the skull, vertebral column, and rib cage Appendicular skeleton – bones of upper and lower extremeties and girdles (shoulder/hip)

28. A. Skull – body’s most complex bony structure – Fig. 6-8 1. Cranial bones (8) a. site of attachment of head muscles b. enclose & protect brain & organs of hearing & equilibrium

30. 2. Facial bones (14) a. form framework of face b. hold eyes in an anterior position c. provide cavities for the organs of taste & smell and openings for the passage of air & food d. secure teeth e. anchor the facial muscles of expression

32. 3. Middle ear bones (6) – used in sense of hearing

33. 4. Sutures – interlocking joints of skull bones

34. B. Vertebral column – 26 irregular bones that form a flexible curved rod that supports the body trunk 1. Provides attachment points for ribs & muscles of back 2. Division of spine – curvature increases strength, resilience & flexibility of spine, making it function like a spring rather than a rod

36. C. Thorax – 12 pairs of ribs (both male & female), sternum, thoracic vertebrae, costal cartilage 1. Forms protective cage around thoracic organs 2. Supports shoulder girdles & upper limbs 3. Provides attachment points for the muscles of the back, chest, & shoulders 4. Intercostal spaces – occupied by inter- costal muscles which elevate & depress during breathing

38. A. Adapted to carry out movement B. Pectoral (shoulder) girdle – clavicle, scapula C. Arm/hand – humerus, radius, ulna, carpals, metacarpals, phalanges D. Pelvic girdle – coxal bones (ilium, ischium, pubic) E. Leg/feet – femur, tibia, fibula, patella, tarsals, metatarsals, phalanges

43. A. Most male skeletons are larger (no great functional importance) B. Structural difference in pelvis 1. Male - narrower 2. Female – structured to cradle baby; broader, shallower, lighter, rounder C. Pelvic brim 1. Male – basically heart shaped 2. Female – wider, oval from side to side D. Coccyx 1. Male – narrow, longer; less movable; curves ventrally 2. Female – wider, shorter; more movable; straighter

46.  Two different ways to classify Structural classification – based on material that binds fibrous cartilaginous synovial Functional classification – based on amount of movement

47. Synarthroses – immovable joints; fibrous connective tissue grows between the articulating bones; - ex. Sutures of cranial bones

48. Amphiarthroses – slightly moveable; cartilage or fibrous tissue connects articulating bones – ex. Symphysis pubis, ligaments, fibrous membrane between radius & ulna

49. Diarthroses – allow considerable movement; Fig. 6-20, 6-21, Table 6-7 1. Ball & socket a. shoulder & hip joints b. this type of joint permits the widest range of motion

50.  Diarthroses – allow considerable movement; Fig. 6-20, 6-21, Table 6-7 2. Hinge joints a. elbow & knee, fingers, toes b. movement in 2 directions – flexion (bending), extension (straightening)

51. Diarthroses – allow considerable movement; Fig. 6-20, 6-21, Table 6-7 3. Pivot joint a. small projections of one bone pivots in an arch of another b. C 2 (axis) projection pivots in arch of C 1 (atlas); allows rotation of the head

52. Diarthroses – allow considerable movement; Fig. 6-20, 6-21, Table 6-7 4. Saddle Joint – only 1 pair a. between metacarpal bone of thumb & carpal bone of the wrist b. produces great mobility (opposable thumb);  flex & extend  Abduct – moving away from midline  Adduct – moving toward midline  Circumduct - circle

54. Diarthroses – allow considerable movement; Fig. 6-20, 6-21, Table 6-7 5. Gliding – flat surfaces a. least movable of all diarthrotic joints b. joint between vertebrae or between & carpal/tarsal bones

55. Diarthroses – allow considerable movement; Fig. 6-20, 6-21, Table 6-7 6. Condyloid joints (ellipsoid) a. condyle fits into an elliptical socket b. ex. – distal end of radius & carpal bones or femur & tibia