Skeletal System
The framework of bones in the body, consisting of 206 bones in adults.
Axial Skeleton
The part of the skeletal system connected to the vertebrae and spinal column, including the skull, spine, ribs, and sternum.
Appendicular Skeleton
The part of the skeletal system that branches off the axial skeleton, including the shoulder and pelvic girdles and attached limb bones.
Functions of the Skeletal System
Body movement, support and protection of internal organs, production of red and white blood cells, and mineral storage.
Osteocytes
Mature bone cells that make up bone tissue.
Organic Material in Bones
Comprises 35% of bone composition.
Inorganic Mineral Salts and Water
Comprises 65% of bone composition.
Osteoclasts
Cells that break down bone tissue.
Osteoblasts
Cells that build up bone tissue.
Bone Formation
Begins with collagenous protein fibers secreted by osteoblasts, followed by cartilage deposition and ossification.
Epiphysis
The ends of a long bone.
Diaphysis
The middle shaft of a long bone.
Growth Plate
The area that divides the epiphysis and diaphysis; an open _____ indicates that the bone is still growing.
Medullary Cavity
The hollow space within the diaphysis that contains bone marrow.
Periosteum
The outer covering of the diaphysis of a bone.
Long Bones
Bones found in the upper and lower arms and legs.
Short Bones
Cube-like bones.
Flat Bones
Bones that make up the skull and ribs.
Irregular Bones
Bones that make up the spinal column; most flat bones are also _____.
Joint Movement
The degree of movement at a joint is based on bone shape and joint structure.
Simple Fracture
A fracture that does not break through the skin.
Compound Fracture
A fracture where the fractured end penetrates the skin, posing a risk of infection.
Greenstick Fracture
A type of fracture common in children due to their more flexible bones.
Comminuted Fracture
A fracture where the bone shatters in three or more places.
Stress Fracture
A fracture caused by overuse, poor muscle balance, lack of flexibility, or previous injuries.
Epiphyseal Plate
A growth plate more commonly found in children aged 10-16, often affected by sports participation.
Fracture Symptoms
Not all fractures result in visible deformity.