A&P, Tort, Ch 6 skeletal system - bone tissue

articular cartilages

...(hyaline cartilage) cover the epiphyses, end of bone, attaches to articular bone surfaces

medullary canal

..., A narrow space or cavity throughout the length of the diaphysis of bone, contains yellow marrow

endosteum

..., Connective tissue membrane lining the inside of the medullary cavity and the outside of the yellow bone marrow, osteogenic cells and osteoclasts

yellow marrow

..., Functions as a fat storage area, is composed chiefly of fat cells and is located in the medullary cavity

spongy bone

..., Lightweight bone tissue that makes up the interior of bones. Consists of an irregular latticework of trabeculae containing many spaces filled with red bone marrow. Also called CANCELLOUS bone.

fracture hematoma

..., a mass of clotted blood that forms around the site of a bone fracture within 6-8 hours after the injury

dense bone

..., also called compact bone, , the long part of long bones, in which yellow marrow is found and stores fat

periosteum

..., connective tissue, vascular membrane covering shaft of bone, with osteogenic cells and osteoclasts

intramembranous ossification

..., the process of bone formation in the where bone forms directly within mesenchyme arranged in sheetlike layers that resemble membranes, ie: flat bones of the skull and mandible,

red marrow

..., thick, highly vascularized, blood-like material found in flat bones and the ends of long bones; location of blood cell formation

bone remodeling & stress

...of the callus is accomplished as compact bone replaces spongey bone around the periphery of the fracture, working in toward middle. What we see now is the thickened, healed area where the fracture once was, probably stronger than before fracture in this area.

bony callus

...osteogenic cells produce spongy bone trabeculae, in time is called a boney callus.

fibrocartilage callus

...the periosteum's fibroblasts attack produce collagen fibers; same time chondroblasts from the periosteum and produce fibrocartilage, building a fibrocartilaginous tissue bridges across the bone break, this process takes about 3 weeks.

bone healing, 4 stages

1. Forms hematoma - broken bone tore blood vessels inside, as they then bled, formed blood clots around the fracture, bone cells without normal blood vessel nourishment die, Phagocytes and osteoclasts start to remove debris. within 6 to 8 hours and can last several weeks. 2. Fibrocartilaginous callus forms. the periosteum's fibroblasts attack produce collagen fibers; same time chondroblasts from the periosteum and produce fibrocartilage, building a fibrocartilaginous tissue bridges across the bone break, this process takes about 3 weeks. 3. Boney Callus Formation. osteogenic cells produce spongy bone trabeculae, in time is called a boney callus. 4. Bone remodeling of the callus is accomplished as compact bone replaces spongey bone around the periphery of the fracture, working in toward middle. What we see now is the thickened, healed area where the fracture once was, probably stronger than before fracture in this area. (text p186)

4 classes of Bone Cells

1. long bones (which make up the limbs), 2. short bones (which are grouped together to strengthen our skeleton), 3. flat bones (which protect our body and provide a place for muscles to attach) 4. irregular bones (those oddly shaped bones that don't fit in other three categories).

% Bone Composition

25% water 25% collagen protein fibers 50% hydoxyapetite mineral matrix

osteocytes

Mature bone cells, develop from osteoblasts, control day-to-day activities (each occupies a lacuna, a pocket sandwiched between layers of matrix

cells

The basic unit of all living things

hydroxyapatite mineral matrix, collagen protein fibers, and water

bone composition

osteoblasts

cell formed from osteogenic cell, participates in bone formationby secreting organic components and inorganic salts

long bone structure and its parts, function

epiphysis, articular cartilage, spongy bone, redbone marrow metaphysis, epiphyseal/plate, diaphysis: endosteum, periosteum, medullary cavity, yellow marrow, compact bone, artery in nutrient foremen (vessel in/out of bone)

fetal bone development, 2 processes

intramembranous and endochondral ossifiction

osteoclasts

large multinuclear cell that resorbs (destroys) bone matrix

osteoprogenitor

stem cells derived from the mesenchyme; they produce another stem cell (committed cell) that matures into an OSTEOBLAST located in the PERIOSTEUM and ENDOSTEUM

epiphysis

the end of a long bone

diaphysis

the main (mid) section, or shaft of a long bone

endochondral ossification

the replacement of/ within hyaline cartilage (developed by mesenchyme) with bone, the most common bone formation process with cartilage present.

ligaments

tissue that connects bone to bone provides stability to joints

tendons

tissue that connects muscle to bone, tissue that connects muscle to bone, cause bone to move with muscle flex