ch7 - skeletal system

Question 1

shapes of bones

Answer 1

long
short
flat
irregular

Question 2

long bones

Answer 2

long longitudinal axes
ie - forearm, thigh bones

Question 3

short bones

Answer 3

equal lengths and widths
ie wrists, ankles

Question 4

sesamoid // round bone

Answer 4

special type of short bone, small and nodular and imbedded in dentond adjace to joint (patella)

Question 5

flat bone

Answer 5

platelike structures with brod surfaces
ie ribs, scapulae some bones of skull

Question 6

irregular bones

Answer 6

variety of shapes and sizes
vertabrea and many facial bones

Question 7

structure of long bone

Answer 7

epiphysis - expanded end
diaphysis - bone shaft
meaphysis - between diaphysis and epihysis. Widening part
articular cartilage - covers epiphysis
periosteum - encloses bone, dense connective tissue (outter layer)
compact bone (cortical) wall of diaphysis
spongy bone (cancellous) makes up the epiphyses
trabeculae - branching bony plates, make up spongy bone
medullar cavity - hollow chamber in diaphysis contains marrow
endosteum - lines spaces, cavity
bone marrow - red or yellow marrow lines medullary cavity and spongy bone spaces

Question 8

osteocytes

Answer 8

mature bone cells

Question 9

lacunae

Answer 9

chambers occupied by osteocytes

Question 10

canaliculi

Answer 10

tiny passageways through which the cell process of osteocytes exchange nutrients and wastes

Question 11

extracellular matrix of bone

Answer 11

largely collagen fibers and inorganic salts
collagen provides resilience and inorganic salt makes bone hard

Question 12

compact bone

Answer 12

consists of microscopic cylindrical units called osteons
osteons and layers of matrix (lamellae) cluster around a central canal
blood vessels and nerves occupyt the central cannal
strong and solid
weight bearing
resists compression

Question 13

spongy bone

Answer 13

consists of branching plates called trabeculae
comewhat flexible
has spaces between trabeculae

Question 14

types of bone marrow

Answer 14

red - produces blood cells
yellow - stores fat

Question 15

regulation of concentration of blood calcium

Answer 15

if levels drop, parathyroid hormone stimulates osteoclasts to break down bone and release calcium
if levels rise, calcitonin stimulates osteoblasts to deposit calcium in the bone

Question 16

cranial bones

Answer 16

frontal - forehead
parietal - side walls and roof
occipital - back of skull
temporal - side walls and floor
sphenoid- part of base skull and floor
ethmoid - part of roof nasal cavity floor of craniom and walls