Bone Physiology Chapter 7 Pages

STRUCTURE: Epiphysis Ends of bones, enlarged for joining with the next bone— proximal and distal

Diaphysis Shaft of the bone Periosteum Membrane attached to bone (tendon/ligament attachment)

Compact Bone Solid, strong-diaphysis Spongy Bone Branching, resists compression-epiphysis

Medullary Cavity Hollow chamber Contains blood vessels and nerves Endosteum Internal lining

Marrow Soft connective tissue Produce blood cells

MICROSCOPIC: Osteonic Canal Contain blood vessels and nerves Osteocytes arranged in circles around the canal

Communication Canals Connect osteonic canals

BONE GROWTH: Page 127 Intramembraneous Bones Broad, flat bones of the skull

Layers of connective tissue become osteoblasts (bone forming cells) When a matrix surrounds osteoblasts & becomes osteocytes

Endochondral Bone Make up most of the bones of the skeleton Mass of cartilage Primary ossification center-diaphysis

Secondary ossification center = epiphysis Cartilage between centers form growth plates

A lot of mitosis (growth) until ossified, cartilage on ends remain

HOMEOSTASIS: Osteoblasts build Osteoclasts dissolve Constantly modify bone

Osteocytes are mature bone cells Blood cell formation= Hematopoiesis

FUNCTIONS: Support, protection, movement

Bone Marrow is found in shaft of long bones, in spaces of spongy bones, and in large osteonic canals of compact bone

Red Marrow forms RBCs Yellow Marrow replaces red with age (inactive in blood cell production), aids in fat storage

Storage of calcium salts Low calcium- osteoclasts break down bone tissue

High calcium-inhibits osteoclasts, osteoblasts are stimulated to form bone tissue