McCance Chapter 44 Structure and Function of the Musculoskeletal System

Amphiarthrosis

Slightly movable joint

Bone albumin

Transports essential elements such as hormones, ions, and other metabolites to and from the bone cells and maintains the osmotic pressure of bone fluid

Bone morphogenic proteins

Multifunctional growth factors in the transforming growth factor-beta (TGF-β) superfamily, affect several systems, including embryonic and postnatal cartilage and bone development.

Callus

Osteoblasts form membranous or woven bone, enzymes increase the phosphate content and permit the phosphate to join with calcium to be deposited as mineral

Canaliculi

Connect the lacunae to each other and to the haversian canal, transport nourishment and molecular signals to osteocytes

Diaphysis

Shaft of thick, rigid compact bone that can tolerate bending forces

Diarthrosis

Freely movable joint

Endosteum

A thin layer of connective tissue that lines the surface of the bony tissue that forms the medullary cavity of long bones

Epiphysis

Rounded end of a long bone, made up of spongy bone covered by a very thin layer of compact bone

Fibrils

Type I collagen fibers grouped in threes

Glycoproteins

Control the collagen interactions that lead to fibril formation

Gomphosis

Fibrous joint in which a conical projection fits into a complementary socket and is held there by a ligament (teeth held in the maxilla or mandible)

Haversian canal

Runs through the long axis of bone and contains one or two blood vessels and nerve fibers.

Hydroxyapatite

Calcium phosphate crystals that form the mineralized portion of bone

Lacunae

Space between the lamellae that contain one osteocyte

Lamellae

Concentric rings of mineralized bone around the haversian canal

Matrix metalloproteinases

Proteolytic enzymes, help control osteoclast-matrix interactions necessary for bone resorption

Osteoblasts

Form new bone

Osteoclasts

Major resorptive cells of bone, secrete hydrochloric acid (HCl) and cathepsin K (a protease enzyme) that dissolve bone minerals and along with collagenase dissolve collagen

Osteocytes

Help maintain bone by signaling osteoblasts and osteoclasts to form and resorb bone, release enzymes that dissolve the mineralized walls of the lacunae to prepare the bone for remodeling

Periosteum

Double layer of connective tissue that covers all bone

Procallus

Fibroblasts, capillary buds, and osteoblasts move into the wound to produce granulation tissue

Proteoglycans

Large complexes of polysaccharides attached to a common protein core, form hylaine cartilage, strengthen bone and control the transport and distribution of electrically charged particles (ions), particularly calcium, through the bone matrix

Suture

A thin layer of dense fibrous tissue that binds together interlocking flat bones in the skull

Symphysis

Cartilaginous joint in which bones are united by a pad or disk of fibrocartilage (symphysis pubis and intervertebral disks)

Synarthrosis

Immovable joint

Synchondrosis

Hyaline cartilage connects the two bones (ex. joints between the ribs and the sternum)

Syndesmosis

Two bony surfaces are united by a ligament or membrane

Synovial Joints

The most movable and the most complex joints

Trabeculae

Lamellae in spongy bone are not arranged in concentric layers but in plates to form an irregular meshwork

Wnt genes

Regulates production and differentiation of osteoblasts and osteoclasts.

Hyaline cartilage

Primarily composed of the glycosaminoglycans chondroitin sulfate and keratin sulfate