Anatomy And Physiology Ch 6 (Bone - Function/structure)

Front 1

bone

Back 1

made of cartilage, dense connective tissue, epithelium, adipose, nervous and osseous tissue

Front 2

osteology

Back 2

study of bone structure and the treatment of bone disorders

Front 3

function of the skeletal system

Back 3

support
protection
assistance in movement
mineral homeostasis
blood cell production
triglyceride storage

Front 4

long bone

Back 4

a bone with greater length than width

Front 5

diaphysis

Back 5

bone's shaft or body

Front 6

epiphyses

Back 6

proximal & distal ends of the long bone

Front 7

metaphyses

Back 7

region in a mature bone where the diaphysis joins the epiphysis includes
epiphyseal plate in a growing bone
epiphyseal line in a mature bone

Front 8

articular cartilage

Back 8

thin layer of hyaline cartilage covering the part of the epiphysis where the bone forms an articulation (joint) with another bone

Front 9

periosteum

Back 9

sheath of dense irregular connective tissue that surrounds the bone surface wherever it is not covered by articular cartilage

Front 10

medullary cavity

Back 10

space within the diaphysis that contains fatty yellow bone marrow in adults
(aka marrow cavity)

Front 11

endosteum

Back 11

thin membrane that lines the medullary cavity

Front 12

composition of bone or osseous tissue

Back 12

widely spaced cells
abundant extracellular matrix which is:
25% water
25% collagen fibers
50% crystallized mineral salts (hydroxyapatite)

Front 13

4 types of bone tissue cells

Back 13

osteogenic
osteoblast
osteocyte
osteoclast

Front 14

osteogenic cells

Back 14

unspecialized stem cells derived from mesenchyme
only bone cells that divide
found along inner periosteum, inner endosteum and blood vessels canals

Front 15

osteoblasts

Back 15

blasts that do not divide
secrete collagen fibers
initiate calcification
trapped in their secretions, they become osteocytes

Front 16

osteocytes

Back 16

mature bone cells
maintain daily metabolism
do not divide

Front 17

osteoclasts

Back 17

huge cells from the fusion of ^50 monocytes
(type of white blood cell)
release lysosomal enzymes and acids
to facilitate resorption

Front 18

resorption

Back 18

breakdown of bone extracellular matrix, part of
normal development, maintenance and repair of bone and
to help regulate blood calcium level

Front 19

compact bone tissue

Back 19

protection and support
resists the stresses produced by weight and movement

Front 20

perforating or Volkmann's
canals

Back 20

transverse openings that allow nerves, blood & lymph vessels to connect with those of the medullary cavity, periosteum and central or haversian canals

Front 21

central or haversian canals

Back 21

canal that runs longitudinally through the bone
surrounded by concentric lamellae

Front 22

concentric lamellae

Back 22

rings of calcified extracellular much like the rings of a tree trunk

Front 23

lacunae

Back 23

"little lakes"
in bone tissue they are found between the lamellae and contain osteocytes
of the osteocyte

Front 24

canaliculi

Back 24

small channels filled with extracellular fluid and
fingerlike projections of the osteocyte
they radiate in all directions from the lacunae
neighboring osteovytes communicate via gap junctions forming an intricate system of canals

Front 25

osteon or
haversian system

Back 25

repeating units of a central canal with its concntrically arranged lamellae, lacunae, osteocyte and canaliculi
aligned in the same direction as the lines of stress in a long bone

Front 26

interstitial lamellae

Back 26

areas between osteons

Front 27

circumferentail lamellae

Back 27

lamellae that encircle the bone just beneath the periosteum or encircle the medullary cavity

Front 28

spongy bone tissue
anatomy

Back 28

does not contain osteons
osteocytes in irregularly arranged lacunae,
surrounded by lamella in an irregular lattice of thin columns called trabeculae- macroscopic spaces between trabeculae make bone lighter and give it a "spongy" appearance

Front 29

spongy bone tissue
physiology

Back 29

trabeculae are precisely oriented along lines of stress where bone stress is not heavy
they support and protect the red bone marrow where hemopoeisis occurs in adults