Overview of Skeleton: Learn Skeleton Anatomy

Introduction

• The skeleton provides the body’s framework, facilitating movement and structure.
• Consists of more than 200 bones, cartilage, and ligaments.

Key Facts About the Human Skeleton

1. Composition

• Human skeleton includes bones, ligaments, and cartilage.
• Ligaments are dense connective tissue aiding joint function.
• Cartilage provides flexibility and structure, found in the larynx, nose, and between vertebrae.

2. Bone Count

• Adult human skeleton comprises 206 bones.
• Bones form crucial structures: skull (brain protection), thoracic cage (heart and lungs), and vertebral column (spine).
• Limbs and girdles attach to the vertebral column.

3. Protection of Vital Organs

• Skull protects the brain.
• Thoracic cavity houses heart and lungs.
• Vertebral column shelters the spinal cord.

4. Movement

• Muscles attached to bones, with nerves signaling movement.
• Skeletal muscles contract upon nervous system commands, enabling joint movement.

5. Axial vs. Appendicular Skeleton

• Appendicular skeleton: facilitates movement (limbs and girdles).
• Axial skeleton: protects internal organs (skull, vertebral column, thoracic cage).

6. Bone Classification

• Five types of bones: long, short, flat, irregular, sesamoid.
• Examples: Femur (long), Frontal (flat), Patella (sesamoid), Carpals (short).

7. Structure of Long Bones

• Consist of compact and spongy bone.
• Contain medullary cavity filled with yellow bone marrow.

8. Red Blood Cell Production

• Occurs in red bone marrow within spongy bone tissue.
• Bones involved: cranium, vertebrae, scapulae, sternum, ribs, pelvis, and ends of large long bones.

9. Joint Movements

• Joints classified by motion range: immovable (skull sutures), slightly movable (distal tibia-fibula), highly movable (shoulder, wrist, hip).

10. Infant Skeleton

• More bones than adults, due to bone fusion over time (e.g., sacrum).

External Resources

• National Cancer Institute: Introduction to skeletal system.
• Mayo Clinic: Tips for maintaining bone health.
• Visible Body Web Suite: 3D anatomy models.

Related Topics

• Types of Bones
• Axial Skeleton
• Appendicular Skeleton
• Joints and Ligaments
• Skeletal System Pathologies

Conclusion

• The skeletal system is essential for structure, protection, movement, and physiological functions like blood cell production.