BIOL235_Chap6 Flashcards
bone remodeling
the continual process of building new bone tissue and breaking down old bone tissue.
bone
organ made up of several different tissues working together (bone (osseous) tissue, cartilage, dense connective tissue, epithelium, adipose tissue + nervous tissue.)
skeletal system
the entire framework of bones and their cartilages
osteology
study of bone structure and treatment of bone disorders
Basic functions of the skeletal system
-support
-protection
-assistance in movement
-mineral homeostasis (storage + release)
-blood cell production
-triglyceride storage
Hemopoiesis
process by which red bone marrow produces red blood cells, white blood cells and platelets
with age, red bone marrow turns into…
yellow bone marrow
long bone
bone of greater length than width and consists of:
diaphysis
epiphyses
metaphyses
articular cartilage
periosteum
medullary cavity
endosteum
articular cartilage
thin layer of hyaline cartliage covering the epiphysis where bone forms articulation with another bone.
reduces friction and absorbs shock
diaphysis
bone’s shaft or body - the cylindrical/main portion
metaphyses
bone region betw. diaphysis + epiphyses, contains epiphyseal (growth) plate,
allows bone to grow in length
epiphyseal plate is replaced by bone once the body gets old and bone stops growing, this bony structure is the epiphyseal line
epiphyses
the proximal + distal ends of the bone
periosteium
tough connective tissue sheat and blod supply that surrounds bone surface wherever not covered by articular cartiliage.
composed of: outer fibrous layer + inner osteogenic layer
attached to underlying bone by perforating fibers/sharpey’s fibers
Perforating fibers = sharpey’s fibers
thick bundles of collagen that extend from the periosteum into the bone extracellular matrix and are the way the periosteum is attached to underlying bone
medullary cavity = marrow cavity
hollow cylindrical space inside diaphysis of bone that contains fatty yellow bone marrow and blood vessles in adults.
reduces bone weight
bone
osseous tissue
endosteum
thin membrane that lines the medullary cavity of bone. contains a layer of bone-forming cells and some connective tissue
osteoblasts
bone-building cells
secretes extracellular matrix and gets trappedn in secretions and becomes osteocytes
hydroxyapatite
crystal combination of calcium phosphate and calcium hydroxide that is the most abundant mineral salt
calcification
process by which hydroxyapatite crystals react with other things to harden tissue and is initiated by bone-building cells call osteoblasts
osteoblasts
bone-building cells
4 types of cells in bone tissue
osteoprogenitor cells
osteoblasts
osteocytes
osteoclasts
osteoprogenitor cells
unspecialized bone stem cells
undergo cell division and result in osteoblasts
along the innder portion of the periosteum, in the endosteium, and in canals within bone that contain blood vessels
-only cells that undergo division
osteocytes
mature bone cells
daily metabolism
cell maintains and monitors bone tissue
osteoclasts
huge cells from fusion of lots of monocytes (type of white blood cells)
in endosteum
does bone resorption
cell breaks down extracellular matrix
target cells for osteoporosis treatement
monocytes
type of white blood cell
bone resoprtion
breakdown of extracellular matrix
by cells ending in -clast
osteoBlasts Build bone
osteoClasts Carve out bone
Compact bone tissue
few spaces betw cells and extracellular matrix
beneath periosteum
bulk of diaphyses of long bones
composed of osteons
osteons = haversian systems
concentric lamellae arrange around an osteonic (haversian or central) canal
concentric lamella
in osteons
look like tree rings
circular plates of minearlized extracellular matrix of inc diameter