Skeletal System

1. Skeletal System Chapter 7

2. Bellringer • What is the purpose of a house frame? • Set up a venn diagram to compare a house frame to the human skeletal system?

3. Functions of the Skeletal System • Bones shape, support, and protect body structures • Aid body movements • House tissues that produce blood cells • Serves as points of muscle attachment • Storehouse of minerals

4. Bellringer • What do you know about the structure of bones? • Recall from biology that birds have hollow bones. What are the advantages of having hollow bones? • Which do you think would be stronger, hollow bones or solid bones?

5. Activity • Roll up 3 pieces of paper so they are about 1 inch wide. • Stand them on end and place a paper plate on top of them. • Add weight until they collapse. How much weight did they hold? • Repeat, rolling the paper up as tightly as possible, so there is no hollow middle. How much weight could they support?

6. Bone Structure • Bones differ greatly in size and shape, but are similar in structure. • Broader area at the ends is called the “epiphysis”. • Epiphysis is covered with hyaline cartilage (???) called “articular*** cartilage”. • The shaft of the bone is called the “diaphysis”.

7. Bone Structure, continued…. • “periosteum” = ??? • Periosteum is a vascular (???) covering of fibrous tissue that completely covers the bone, except for the articular cartilage on the ends. • Tendons and ligaments attach to the periosteum. • Helps form and repair bone tissue.

8. Bone Structure, continued…. • Compact bone (cortical bone) • Tightly packed • Continuous matrix with no gaps • Makes up the walls of the diaphysis • Spongy bone (cancellous bone) • Consists of branching bony plates with connecting spaces, which reduce weight • Makes up the epiphyses (plural form), with thin layers of compact bone on their surfaces

9. Some bones have more dense spongy bone than others. WHY?

10. Bone Structure, continued…. • “Medullary cavity” – hollow chamber in the diaphysis that is continuous with (???) the spongy bone (located where?) • “endosteum” = ? • Endosteum is a thin layer of cells lining the medullary cavity. • “Marrow” – specialized type of soft _______ tissue that fills the cavity.

11. Label Diagram Handout

12. Skull • Usually consists of 22 bones, all of which (except the lower jaw) are firmly interlocked along lines called “sutures”. • Cranium = 8 bones • Facial skeleton = 13 bones + lower jaw • Lower jaw bone is called the mandible, and is the only movable bone.

13. Cranium • Functions: • Encloses and protects the brain • Provides attachments for muscles that make chewing and head movement possible • Has air-filled, mucous-membrane-lined (??), sinus cavities

14. Cranial Bones • Frontal bone • Parietal bones (2) • Occipital bone • Temporal bones (2) • Sphenoid bone • Ethmoid bone

15. Cranial Bones, continued….. • Frontal bone • Anterior portion of skull above the eyes • Houses 2 frontal sinuses, one above each eye near the midline • Parietal bones • One on each side of the skull just behind the frontal bone • Form bulging sides and roof of cranium • Fused at midline (sagittal suture) and to frontal bone (coronal suture)

16. Cranial Bones, continued….. • Occipital bone • Joins the parietal bones (lambdoidal suture) • Forms back of skull and base of cranium • Foramen magnum – opening at bottom of occipital bone for nerve processes to connect to spinal cord • Occipital condyles – rounded processes on each side of foramen magnum that articulate with 1st vertebra

17. Cranial Bones, continued….. • Temporal bones • On each side of the skull • Joins parietal bone (squamosal suture) • Form parts of sides and base of cranium • External auditory meatus(???) • Mandibularfossae– depressions in the temporal bone that articulate with condyles(???) of the mandible

18. Cranial Bones, continued….. • Temporal bones, continued…. • Below each external auditory meatus: • Mastoid process – rounded attachment for certain neck muscles • Styloid process – long, pointed anchor for muscles associated with tongue and pharynx • Zygomatic process • Projects anteriorly(???) from temporal bone, joins the zygomatic bone (“cheek bone”), and helps form prominence of the cheek

19. Cranial Bones, continued….. • Sphenoid bone • Wedged between several other bones in anterior portion of cranium • Has a central portion and 2 wing-like structures that extend laterally (???) • Helps form base of cranium, sides of skull, and sides of orbits (“eye sockets”) • Midline of sphenoid bone has a depression (sellaturcica) that houses pituitary gland • Contains 2 sphenoidal sinuses

20. Cranial Bones, continued….. • Ethmoid bone • Located in front of sphenoid bone • Consists of 2 masses, one on each side of nasal cavity • Masses joined by thin cribriform plates (???) • Cribriform plates form part of nasal cavity roof. • Cristagalli – triangular process between cribriform plates • Perpendicular plate • projects downward from cribriform plates • helps form nasal septum

21. Cranial Bones, continued….. • Ethmoid bone, continued….. • Superior nasal concha and middle nasal concha - project inward from lateral portions of ethmoid bone toward perpendicular plate • Lateral portions of ethmoid bone contain small air spaces (ethmoidal sinuses)

22. Facial Skeleton • Maxillae (2) • Form the upper jaw • Portions comprise the anterior (???) roof of the mouth (“hard palate”), the floors of the orbits (???), and the sides and floor of the nasal cavity. • Contain sockets of the upper teeth • “Maxillary sinuses” • Inside the maxillae, lateral (???) to nasal cavity • The largest of the sinuses

23. Facial Bones, continued…. • Maxillae, continued…. • “Palatine processes” fuse midline (???) to form anterior section of hard palate • Teeth are found in cavities in the “alveolar arch” (aka “dental arch”) formed by the “alveolar processes” projecting downward from the inferior (???) border of the maxillae.

24. Facial Bones, continued…. • Palatine bones • Behind the maxillae • Horizontal portions form posterior (???) section of hard palate and floor of nasal cavity • Perpendicular portions help form lateral (???) walls of nasal cavity

25. Facial Bones, continued….. • Zygomatic bones (“???”) • Also help form lateral walls and floors of the orbits • Each bone has a “temporal process” that connects to the zygomatic process (forming the zygomatic arch). • Lacrimal bones • Thin, scale-like structure in medial wall (??) of each orbit between ethmoid bone and maxilla

26. Facial Bones, continued….. • Nasal bones • Long, thin, and nearly rectangular • Lie side by side and fused at midline to form bridge of nose • Vomer bone • Thin and flat • Along midline in nasal cavity • Joins perpendicular plate of ethmoid bone posteriorly (???) to form nasal septum

27. Facial Bones, continued….. • Inferior nasal conchae • Fragile, scroll-shaped bones attached to lateral walls (???) of nasal cavity • Support mucous membranes in nasal cavity • Mandible (“???”) • Upward projection at ends: • Posterior “mandibular condyle” articulates with mandibular fossae on _______ bone • Anterior “coronoid process” provides attachments for muscles for chewing • “Alveolar arch” – curved, superior (???) border that contains sockets for lower teeth

28. Vertebral Column & Thoracic Cage • Note-taking guide • Marieb’s worksheets

29. Appendicular Skeleton

30. Pectoral Girdle • Clavicle – collarbone • Anterior attachment (?) • Posterior attachment (?) • Scapula – shoulder blades • Posterior attachment (?) • Spine – divides posterior surface into 2 sections • Coracoid process (“Corac” = ?) – curves to clavicle • Acromion process – forms tip of shoulder • Glenoid cavity (or fossa) – depression that articulates with head of humerus

31. Label Diagrams

32. Upper Limb • Humerus • Radius • Ulna • Carpals • Metacarpals • Phalanges

33. Humerus • Head fits into glenoid cavity of scapula • Greater tubercle – lateral process • Lesser tubercle – more anterior process • Intertubercular groove – narrow furrow “between tubercles” • Deltoid tuberosity – v-shaped, rough area where _________ muscles attach to humerus • Olecranon fossa – posterior depression that receives an ulnar process when elbow is straightened • Coronoid fossa – anterior depression that receives a radial process when elbow is bent

34. Radius • Shorter bone of lower arm • Located on thumb side of arm • Disc-like head articulates with humeru and with radial notch of the ulna (so your arm can rotate) • Radial tuberosity, a process below the head, provides attachment for biceps • Styloid process – at distal end; attachment for wrist ligaments

35. Ulna • Longer than radius • Overlaps distal end of humerus posteriorly • Proximal end has a wrenchlike opening called the trochlear notch (articulates w/humerus) • Oleacronon process – top process • Coronoid process – bottom process • Radial notch – just below trochlear notch • Head – at distal end; articulates with ulnar notch of radius • Styloid process – attachment for wrist ligaments

36. Label Diagrams

37. Wrist • Wrist made of 8 carpal bones • “Some lovers try positions that they can’t handle.” • Scaphoid Lunate Triquetrum Pisiform Trapezium Trapezoid Capitate Hamate

38. Hand • 5 metacarpals • Numbered 1-5, starting at thumb • Bones between wrist (carpals) and fingers (?) • Rounded distal ends form knuckles • Each finger, except thumb, has 3 phalanges: • Proximal phalanx • Middle phalanx • Distal phalanx • Thumb only has no middle phalanx.

39. Pelvic Girdle • Composed of sacrum, coccyx, and 2 coxae (hipbones) • Coxae have 3 distinct parts: • Ilium • Ischium • Pubis

40. Pelvic Girdle, continued….. • Coxae parts fuse together in the acetabulum, a cup-shaped area on the lateral surface of the hip that receives the head of the femur.

41. Ilium • Largest and uppermost portion of the coxa • The upper edge is called the iliac crest • Joins the sacrum at the sacroiliac joint • Anterior superior iliac spine-the bony prominence you feel as your “hipbone”

42. Ischium • Forms the lowest portion of the coxa • Ischial tuberosity • Points posteriorly AND downward • Supports the weight of the body when sitting • Ischial spine – a sharp projection above the ischial tuberosity, near the junction of the ischium and ilium

43. Pubis • Anterior portion of the coxa • Two pubic bones join midline at the symphysis pubis joint • Pubic arch • Angle formed by pubic bones below the symphysis pubis • Arch is wider in females

44. Female vs. Male Pelvis

45. Lower Limb • Femur • Patella • Tibia • Fibula • Tarsals • Metatarsals • Phalanges

46. Femur • Longest and strongest bone in the body • Head at top fits into __________of coxa • Greater trochanter – superior, lateral process • Lesser trochanter – inferior, medial process • Distal end: • Two rounded processes posteriorly: lateral condyle and medial condyle • Patella articulates anteriorly

47. Tibia • aka, “shin bone” • Proximal end: • Medial and lateral condylesare concave and articulate with condyles of the femur • Tibial tuberosity just below the condyles; attachment point for patellar ligament • Distal end: medial malleolus forms prominent bony point of inner ankle

48. Fibula • Proximal: head • Articulates with tibia just below the lateral condyle • DOES NOT enter into knee joint or bear any weight • Distal: lateral malleolus forms outer prominent bony part of ankle

49. Ankle (Tarsals) • “Tiger Cubs Need MILC” • Talus (A) Calcaneus (“heal bone”) (K) Navicular (B) Medial cuneiform (D) Intermediate cuneiform (C) Lateral cuneiform (I) Cuboid (J)

50. Side View of the Bones of the Foot