Bones: These are the most obvious part of the skeletal system. There are 206 bones in the adult human body, which can be categorized into:
* Axial Skeleton: This includes the bones that form the central axis of the body:
* Skull (including the mandible)
* Vertebral column (spinal column)
* Ribs
* Sternum (breastbone)
* Appendicular Skeleton: This includes the bones of the limbs and the girdles that attach them to the axial skeleton:
* Shoulder girdle (scapula and clavicle)
* Upper limbs (humerus, radius, ulna, carpals, metacarpals, phalanges)
* Pelvic girdle (hip bones)
* Lower limbs (femur, patella, tibia, fibula, tarsals, metatarsals, phalanges)
Cartilage: This is a strong, flexible connective tissue that:
* Covers the ends of bones at joints to reduce friction
* Forms the framework for the nose, ears, and trachea
* Acts as a shock absorber in the intervertebral discs of the spine
Ligaments: These are tough, fibrous connective tissues that connect bones to each other, providing stability to joints.
Tendons: These are strong, fibrous connective tissues that connect muscles to bones, allowing for movement.
Bone Marrow: Found within the hollow spaces of many bones, it produces blood cells.
Joints: These are the points where two or more bones meet, allowing for movement and flexibility.
It's important to remember that the skeletal system isn't just a collection of hard, inert parts. It's a dynamic system that works with other body systems like the muscular system and the nervous system to provide support, protection, and movement.
