Cumulative Exam Part 3 Flashcards
What are the 6 functions of bones?
Support framework, store and release minerals, storage of energy, hematopoiesis, external protective covering, assistance in movement
What makes up the dense matrix?
1/4 water, 1/4 collagen fibers, 1/2 hydroxyapatite crystals
Part of the matrix that bends slightly, will not tear when pulled, provides skeleton with flexibility
Collagen fibers
Part of the matrix that resists applied pressure without breaking, provides hardness of skeleton
Hydroxyapatite crystals
Shaft of bone
Diaphysis
Central space in bone
Medullary cavity
Ends of bones
Epiphysis
Separates diaphysis from epiphysis, grows in length and made of hyaline cartilage
Epiphyseal plate
Small area between diaphysis and epiphysis
Metaphysis
Cover ends of epiphyses; made of hyaline cartilage
Articular cartilage
Fibrous outer layer; osteogenic inner layer; does not cover articular cartilage
Periosteum
Contains yellow bone marrow
Medullary cavity
Bone marrow in developing bones of fetus and newborn, around spongy bone in adults
Red bone marrow
What is the function of red bone marrow?
Hematopoiesis
Bone marrow in medullary cavities in adults
Yellow bone marrow
What is the function of yellow bone marrow?
Lipid storage
Stem cells that divide to produce osteoblasts
Osteogenic cells
Where are osteogenic cells located?
Inner layer of endosteum and periosteum
Immature bone cells that secrete bone matrix
Osteoblasts
Mature cells that maintain matrix and repair damaged bone
Osteocytes
Breaks down bone matrix
Osteoclasts
What is compact bone made up of?
Osteons
What does the central canal contain?
lymphatic vessels, blood vessels, nerves
Circular layers of bone matrix
Concentric lamellae
Osteocytes are housed in
Lacunae
Canals that interconnect lacunae of an osteon. Nutrients and oxygen pass through
Canaliculi
Fills in space between osteons in compact bone; older osteons partially removed by bone remodeling
Interstitial lamellae
Where is spongy bone found?
Inside of long bones and flat bones
Lamellae form an open network of struts that have no blood vessels
Trabeculae
What are open spaces between trabeculae filled with?
Blood, lymphatic vessels, nerves, red bone marrow
How are substances transported to/from osteocytes in spongy bone if there is no canal with blood?
Through canaliculi that open onto surface of trabeculae
What is the function of compact bone?
Stress in 1 direction
What is the function of spongy bone?
Multidirectional stress
Stimulates osteoclasts; decrease calcium loos by kidneys, enhances effect of calcitriol; increases blood calcium levels
PTH
Activates osteoblasts; promotes calcium loss by kidneys, acts to decrease calcitriol levels; decrease blood calcium levels
Calcitonin
2 bones meet or join
Joint
What determines the direction and distance of movement (ROM)
Joint structure
What are the 4 structural classifications of joints?
Bony fusion, fibrous joint, synovial joint, cartilaginous joint
Bones fuse together
Bony fusion
Bones are interlocked by dense connective tissue
Fibrous joint
Bones are interlocked by cartilage
Cartilaginous joint
Bones connected by a connective tissue capsule that surrounds a lubricated cavity
Synovial joint
What are the 3 functional classifications of a joint?
Synarthrosis, amphiarthrosis, diarthrosis
No movement
Synarthrosis
Little movement
Amphiarthrosis
Freely movable
Diarthrosis