Boens Flashcards
Bone tissue
The primary connective tissue of the skeleton
Where do Osteocytes live
Spaces called lacunae
Ligaments
Attach bones to bones at joints
Hyaline cartilage
Found in the embryonic skeleton, on the ends of bones at joints, in growth plates of long bones, in the ribcage, and in the nose
Fibrocartilage
Forms intervertebral discs between vertebrae
Chondrocytes
Scattered among dense bundles of collagen fibers within the extracellular matrix
Extracellular matrix
15% water, 55% crystallized mineral salts, 30% collagen fibers
Bone tissue
Is connective tissue, is vascular and is innervated
Bone tissue may be categorized as:
Compact bone and Spongy bone
Compact bone
Solid bone found at the surface, consists of repeating column-shaped structural units called osteons
Osteons
Consist of a central (haversian) canal surrounded by concentrically arranged extracellular matrix lacunae, osteocytes, and canaliculi
Perforating canals
penetrate deep into the compact bone from the outside of the bone, connect with central canals that run lengthwise in the compact bone
Concentric lamellae
Arranged like the growth rings of a tree trunk,
Between the lamellae are small spaces called
Lacunae
Canaliculi
Connect lacunae with the central canal, forming a system of interconnected canals
Gap junctions
Connect neighboring osteocytes via tiny fluid-filled protein tunnels
Spongy bone
deep to the compact bone tissue, has a spongy appearance, and gives the bone strength without added weight
Trabeculae
spongy bone is arranged in a latticework of thin columns and beams
Hemopoiesis
occurs in the red bone marrow of spongy bone
Diaphysis
The long shaft of a long bone contains the medullary cavity, which contains yellow bone marrow and blood vessels
Epiphysis
Ends of the long bone: proximal and distal epiphyses
Articular cartilage
is the hyaline cartilage that covers the ends of the epiphyses
Metaphysis
the region between the epiphysis and diaphysis on each end of a long bone
Epiphyseal line
The cartilage in the epiphyseal growth plate is replaced with bone at 18-21 years of age and becomes the epiphyseal line
Arteries
Supply oxygen and nutrients to the periosteum and bone
Veins
Carry blood and waste away
Periosteum
A tough membrane that covers the bone
The outer fibrous layer of the periosteum
made of dense irregular connective tissue
Inner osteogenic layer
contains cells involved in bone growth and breakdown
Endosteum
A membrane that covers the bone surface on the inside wall of the medullary cavity and on the surface of spongy bone
What are the 3 types of cells that are present in the endosteum and inner osteogenic layer of the periosteum
Osteogenic cells, osteoblasts, osteoclasts
Osteogenic cells
are bone stem cells that develop from the mesenchymal cells remain in the periosteum and endosteum, undergo cell division, and develop into osteoblasts
Osteoblasts
Bone-building cells
Calcification
Initiated by the osteoblasts
Osteoclasts
release H+ ions and enzymes that break down the bone matrix
Ossification
The process by which bone forms: Formation of bone in an embryo, Growth of bones during childhood, remodeling of bone, repair of fractures
Intramembranous ossification
flat bones of the skull and the mandible are formed in this way, mesenchyme membranes are converted to bone
Endochondral ossification
The replacement of cartilage by bone
Fontanels
remain between the bones of the skull at birth, the larger spaces between the infant’s cranial bones
Endochondral ossigication
