Chapter 6: Bone Tissue
Medullary Cavity
large cavity within the diaphysis
Red Marrow
connective tissue in the spaces of spongy bone or in the medullary cavity; the site of blood cell production
Spongy Bone
consist of interconnecting rods or plates or bone called "trabeculae"; between the trabeculae are spaces, which in life are filled with bone marrow and blood vessels
Osteoblasts function
Produce collagen and proteoglycans Secrete matrix vesicles
Articular Cartilage
a type of hyaline cartilage that covers the end of a long bone
perichondrium
double-layered outer layer of dense irregular connective tissue surrounding cartilage; contains fibroblasts
proteoglycans function
make cartilage resilient by trapping water
Osteocytes
mature bone cells surrounded by bone matrix; housed within the lacunae
Perforating Canals
"Volkmann Canals" deliver blood to the central canals of the osteons; Run perpendicular to the length of the bone; contain blood vessels from the periosteum or medullary cavity
Ossification
"osteogenesis"; bone formation; occurs by appositional growth on the surface of previously existing material (bone or cartilage)
Articular cartilage
Hyaline cartilage that covers the ends of bones where they come together to form joints; has no perichondrium, blood vessels, or nerves
Osteoblasts
bone-building cells; have an extensive ER and numerous ribosomes
Osteoclasts
bone-destroying cells; break down bone
chondroblast
cartilage-producing cell
Perforating Canals
deliver blood to the central canals of the osteons; contain blood vessels from the periosteum or medullary cavity
Yellow Marrow
fat stored within medullary cavity or in the spaces of spongy bone
Circumferential Lamellae
form the outer surface of compact bone, which are thin plates that extend around the bone
Bone Collar
formed by when osteoblasts produce compact bone on the surface of the cartilage
Epiphyseal Plate
hyaline cartilage between the diaphysis and epiphysis; its growth allows for growth in bone length
Lamellar Bone
mature bone; organized into thin, concentric sheets or layers approximately 3-7 micrometers thick called "lamellae"
chondrocyte
mature cartilage cell; rounded cells that occupy a lacuna
Canaliculi
narrow, long spaces where osteocyte cell extensions are housed
Periosteum
out, double-layered connective tissue membrane with ligaments and tendons attached to bone through the periosteum; blood vessels and nerve pathways; the periosteum is where bone grows in diameter
Interstitial Lamellae
remnants of concentric or circumferential lamellae that were partially removed during bone remodeling
Diaphysis
shaft of long bone; the center portion of the bone; composed primarily of compact bone, surrounding a hollow center cavity
lacuna
small space or cavity; potential space within the matrix of bone or cartilage normally occupied by a cell that can be visualized only when the cell shrinks away from the matrix during fixation
Fontanels
soft spots; the larger, membrane-covered spaces between the developing skull bones that have not yet been ossified
Endochondral Ossification
starts with a cartilage model; beings at app. the end of the 4th week of the embryonic development. Bones at the base of the skull, part of the mandible, the epiphyses of the clavicles, and most of the remaining skeletal system develop from this form of ossification
Intramembranous ossification
starts within embryonic connective tissue membranes; starts at app. 2 years of age. Skull bones, part of the mandible, and the diaphysis develop from this for of ossification
Collagen provides:
strength
Central Canal
the "bull's eye" of the target (osteon)
Bone Reabsorption
the breakdown of bone; important for mobilizing crucial Ca+2 and phosphate ions for use in many metabolic processes.
Epiphysis
the ends of a long bone; mostly spongy bone, with an outer layer of compact bone; develops from its own center of ossification
Woven Bone
the first type of bone that osteoblasts form during ossification; fairly weak bone because the collagen fibers are randomly oriented in many directions
interstitial growth
the growth where chondrocytes in the center of the tissue divide and add more matrix in between the existing cells
hyaline cartilage
the most important cartilage since most bones in the body start out as a hyaline cartilage model.
Concentric Lamellae
the rings of bone matrix surrounding the central canal
Compact Bone
the solid, outer layer surround each bone; has more matrix and is denser with fewer pore than spongy bone; appears solid
Endosteum
thin connective tissue membrane lining the inner cavities of bone
Appositional growth
type of growth where chondroblasts in the perichondrium add new cartilage to the outside edge of the existing cartilage