1. II Axial Skeleton (E-F)

2. The Axial Skeleton Forms the longitudinal part of the body
Divided into three parts
Skull
Vertebral column
Bony thorax

3. The Vertebral Column (spine)
Vertebrae separated by intervertebral discs
The spine has a normal curvature
Each vertebrae is given a name according to its location
Figure 5.14

4. Improper Vertebral Curvatures

5. E. Vertebral Column (spine)
1. Cervical (C1 – C7)
C1 – atlas – articulates with occipital condyles of skull; allows you to nod “yes”
C2 – axis – pivots skull; allows you to indicate “no”
Smallest vertebrae
Spinous process is short and branched (forked)
Transverse processes contain foramina for arteries going to the brain

6. E. Vertebral Column (spine)
2. Thoracic (T1 – T12)
Articulate with ribs
Larger than cervical
Spinous process is long and hooks sharply downward
3. Lumbar (L1 – L5)
Largest and sturdiest with massive block like bodies
Spinous process is short and hatchet-shaped

7. E. Vertebral Column (spine)
4. Sacrum
Formed from five fused vertebrae
5. Coccyx
Formed from three to five fused vertebrae
Forms the human “tailbone”

8. Structure of a Typical Vertebrae
Figure 5.16

9. Cervical Vertebrae (C1-C7)
Figure 5.17a–b

10. Thoracic(T1-T12) and Lumbar Vertebrae(L1-L5)
Figure 5.17c–d

11. Coccyx and Sacrum

12. F. Function of Thoracic Cage (Bony Thorax)
1. Protects vital organs such as heart, lungs, and liver
2. Plays a role in breathing
3. Supports the pectoral girdle and arms

13. The Thoracic Cage (Bony Thorax)
Made-up of three parts
Sternum
Ribs
Thoracic vertebrae
Figure 5.19a

14. G. Thoracic Cage (Bony Thorax)
1. Sternum - 3 fused bones which articulate with first 7 pair of ribs
Manubrium- articulates with the clavicle (collarbone)
Body
Xiphoid process
2. Ribs – 12 pair
True ribs (1-7) – 7 pair; attach directly to sternum
False ribs (8-12) – 5 pair; attach indirectly to sternum or not attached at all
Floating ribs (11,12) – 2 pair; lack sternal attachment
3. Thoracic Vertebrae – 12