Skeletal System: Structure and Function

Functions

Support: body structure and shape Protection: vital organs surrounded Movement/Anchorage of Muscles Mineral Storage: calcium & phosphorus Blood Formation

Functions of Bone Support—bones form the framework of the body and

contribute to the shape, alignment, and positioning of the body parts

Protection—bony “boxes” protect the delicate structures they enclose

Movement—bones with their joints constitute levers that move as muscles contract

Mineral storage—bones are the major reservoir for calcium, phosphorus, and other minerals

Hematopoiesis—blood cell formation is carried out by myeloid tissue

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Bone Composition

Collagen: chief organic constituent (protein)

Inorganic Calcium Salts: Vitamin D essential for absorption

Classification of Bones on the Basis of Shape

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Figure 5.1

Long Bones

Extremities Femur, tibia, fibula,

humerus, ulna, radius, clavicle

Levers

Short Bones

Cube-shaped Allows flexible

movement Carpals, tarsals,

metacarpals, metatarsals, phalanges

Flat Bones

Flat Plates Protect Vital Organs Provide Broad Surface

Area for Attachment of Muscles

Cranial Bones, Facial Bones, Scapula, Sternum

Irregular Bones

Peculiarly Shaped to Provide Support and Protection with Flexibility

Vertebrae, Ribs, Ear, Hip, Hyoid

Bone Marrow - Red Hematopoietic Tissue In cancellous bone in children In adults: cancellous bone of vertebrae,

hips, sternum, ribs, cranial bones, proximal ends of femur and humerus

Forms RBCs, platelets, some WBCs and destroys old RBCs and some foreign materials

Axial Skeleton vs. Appendicular Skeleton

Name Those Bones !!

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1. Skull 2. Mandible 3. Sternum 4. Ribs 5. Vertebrae 6. Pelvis 7. - 8. - 9. Carpals 10. Metacarpals 11. Phalanges 12. Femur 13. Patella 14. Fibula 15. Tibia

16. Clavicle 17. Scapula 18. Humerus 19. Radius 20. Ulna 21. Tarsals 22. Metatarsals 11. Phalanges