Flashcards in test 2 ch 6 Deck (33):
1
5 primary functions of the skeletal system
1. support 2. storage of minerals (calcium) and lipids (yellow marrow) 3. blood cell production (red marrow) 4. protection 5. leverage (force of motion)
2
sutural bones
small irregular bones found between the flat bones of the skull
3
irregular bones
complex shapes
vertebrae, pelvis
4
short bones
small and thick
ankle and wrist
5
long bones
long, thin, with rounded ends
arms, legs, fingers, toes
6
sesamoid bones
small, flat, and develop inside tendons
minisci
7
diaphysis
shaft of bone has a heavy wall of compact bone around a central medullary cavity
8
epiphysis
wide part at each end of bone that articulates w other bones. Made up of mostly spongy bone (cancellous) covered with compact bone (cortex)
9
metaphysis
where diaphysis and epiphysis meet
10
structure of flat bone
resembles a sandwich of spongy bone between 2 layers of compact bone; parietal bone
11
diploe
layer of spongy bone between the compact bone in the cranium
12
osseous tissue characteristics
dense, supportive connective tissue that contains specialized cells; produces solid matrix of calcium salt deposits around collagen fibers
13
osteocytes
bone cells within lacunae organized around blood vessels; do not divide; are between lamellae (layers) of matrix and connect by cytoplasmic extensions through canaliculi
14
canaliculi
form pathways for blood vessels to exchange nutrients and waste
15
periosteum
covers outer surface of bone and consists of outer fibrous and inner cellular layers
16
osteoblasts
immature bone cells that secrete matrix compounds (osteogenesis)
17
osteoid
matrix produced by osteoblasts, but not yet calcified to form bone
18
osteoprogenitor cells
mesenchymal stem cells that divide to produce osteoblasts; located in endosteum; assist in fracture repair
19
osteoclasts
giant multinucleated cells that dissolve bone matrix and release stored minerals (osteolysis)
20
trabeculae
open form of matrix found in spongy bone
21
endochondral ossification
ossifies bone that originates from hyaline cartilage
22
appositional growth
compact bone thickens and strengthens long bone w layers of circumferential lamellae
23
epiphyseal lines
when long bones stop growing after puberty
24
intramembraneous ossification
occurs in the dermis and produces dermal bones-mandible and clavicle
25
hormone calcitrol
made in the kidneys and helps absorb calcium and phosphorus from digestive tract; requires vitamin D3 (cholecalciferol)
26
bone growth vit C
collagen synthesis and stimulation of osteoblast defferentiation
27
bone growth vit A
osteoblast activity
28
growth hormone and thyroxine
stimulat bone growth
29
estrogens and androgens
stimulate osteoblasts
30
calcitonin and parathyroid horemone (PTH)
regulate calcium and phosphate levels- increases
31
parathyroid hormone
stimulates osteoblast and osteoclast activity
32
hormone calcitonin
made in thyroid gland; inhibits osteoclast activity, decreases calcium in blood
33