skeletal system n.
Skip this Video
Loading SlideShow in 5 Seconds..
Skeletal system PowerPoint Presentation
Download Presentation
Skeletal system

Loading in 2 Seconds...

  share
play fullscreen
1 / 20
Download Presentation

Skeletal system - PowerPoint PPT Presentation

ilario
120 Views
Download Presentation

Skeletal system

- - - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

  1. Skeletal system Lecture #3

  2. Skeletal organization • Axial skeleton – skull, vertebral column, ribs, sternum • Appendicular skeleton – pectoral girdle, pelvic girdle, limbs

  3. Axial – Skull bones • Cranial – flat bones enclose and protect brain • Frontal bone: forehead and upper ridges of eye sockets • Parietal bones: upper left and right sides of skull • Temporal bones: lower left and right (ears)

  4. Skull bones cont’d • Sphenoid bone: back of the eye sockets • Ethmoid bone: contributes to eye sockets and helps to support the nose • Occipital bone: curves underneath to form the back & base of the skull • Foramen magnum (L. great opening): where vertebrae connects to skull

  5. But wait, there’s moreSkull bones! Facial bones - front • Maxilla – forms part of eye sockets and sockets to anchor upper row of teeth • Palatine bones – hard palate (roof of mouth) • Vomer bone – behind palatine & part of nasal septum

  6. But wait, there’s moreSkull bones! • Zygomatic bones: cheek bones & outer portion of eye socket • Nasal bones: underlie the upper bridge of nose (space between maxilla & nasal bones is the nasal cavity) • Lacrimal bones: inner eye sockets with tear duct (drains to nasal cavity)

  7. All skull bones joined tightly except for mandible (speak & chew) • Mandible: lower jaw w/ sockets for teeth • Sinuses are air spaces which make the skull lighter and give the human voice its tone and resonance • Each sinus is lined with tissue that secretes mucus & connects to nasal cavity by small passageways

  8. Blocked sinuses = pain • Respiratory infections cause sinus tissue to become inflamed and block the passages to the nasal cavity • Sinusitis = sinus inflammation • Fluid gets trapped causing sinus pressure headache

  9. Hyoid Bone – structure & function • U-shaped, superior to larynx in the neck • The only bone that isn’t articulated with another bone • Suspended from styloid processes of temporal bone • Anchors the tongue & serves as attachment for swallowing muscles

  10. Vertebral Column • Skull to pelvis - rib attachment, pelvic girdle attachment • Protects spinal cord as it passes through vertebral canal • 33 vertebrae • 7 neck / cervical • 12 chest / thoracic • 5 lumbar / lower back • 5 sacral • 3-5 tailbone / coccygeal

  11. 4 curvatures • Cervical & lumbar = convex • Thoracic & sacral = concave

  12. Figure 5.7

  13. Thoracic (Rib) Cage • 12 thoracic vertebrae = 12 ribs connect to vertebrae posteriorly • Upper 7 connect directly to sternum via cartilage = true ribs • Lower 5 = false ribs – upper 3 attach to sternum with common cartilage& bottom 2 are not attached to sternum (floating)

  14. Figure 5.9