SKELETAL SYSTEM

Question 1

functions of skeletal system

Answer 1

body support
organ protection
body movement
mineral storage
blood cell production

Question 2

strong bands of fibrous connective tissue, holds bones together

Answer 2

ligaments

Question 3

provides flexibility buts resists pulling or compression

Answer 3

collagen

Question 4

calcium phosphate crystal

Answer 4

hydroxyapatite

Question 5

imperfect bone formation ; rare disorders caused by any one of a number of faulty genes that results in either too little collagen formation or poor quality collagen

Answer 5

brittle bone disease

Question 6

bone building cells ; extensive endoplasmic reticulum and numerous ribosomes

Answer 6

osteoblasts

Question 7

the formation of new bone by osteoblasts called

Answer 7

ossification

Question 8

can occur multiple times during life; fetus and any time when a fracture is repaired

Answer 8

ossification or osteogenesis

Question 9

osteoblasts become _ once osteoblasts have secreted sufficient bone matrix

Answer 9

osteocytes

Question 10

osteocyte cell bodies are housed within the bone matrix in spaces called

Answer 10

lacunae

Question 11

osteocyte cell extensions are housed in narrow, long spaces called

Answer 11

canaliculi

Question 12

bone destroying cells ; break down bone ; develop in the red bone marrow

Answer 12

osteoclasts

Question 13

breakdown of bone is called _ ; important for mobilizing calcium and phosphate ions used for metabolic processes

Answer 13

bone reabsorption

Question 14

osteoclasts develop ; specialized reabsorption specific area of the membrane

Answer 14

ruffled border

Question 15

mature bone

Answer 15

lamellar bone

Question 16

lamellar bone is organized into thin, concentric sheets or layers

Answer 16

lamellae

Question 16

functional unit of compact bone ; composed of concentric rings of matrix, which surround a central tunnel and contain osteocytes

Answer 16

osteon

Question 16

eye of the osteon ; lined with endosteum and contain blood vessels, nerves, and loose connective tissue

Answer 16

central canal

Question 17

solid, outer layer surrounding each bone ; has more matrix and is denser with fewer pores

Answer 17

compact or cortical bone

Question 17

spongy bone consists of interconnecting rods or plates of bone called

Answer 17

trabeculae

Question 17

appears porous, has less bone matrix and more space

Answer 17

spongy bone

Question 18

the center portion of a long bone

Answer 18

diaphysis

Question 19

composed primarily of compact bone tissue surrounding a hollow center called

Answer 19

medullary cavity

Question 20

end of a long bone are called ; mostly spongy bone with an outer layer of compact bone

Answer 20

epiphyses

Question 21

end of long bone is covered with hyaline cartilage

Answer 21

articular cartilage

Question 22

located between epiphysis and diaphysis

Answer 22

epiphyseal plate or growth plate

Question 23

when bone stops growing in length, the plate become ossified

Answer 23

epiphyseal line

Question 24

site of blood cell formation

Answer 24

red marrow

Question 25

mostly adipose tissue

Answer 25

yellow marrow

Question 26

a connective tissue membrane covering the outer surface of a bone

Answer 26

periosteum

Question 27

blood vessels and nerves

Answer 27

outer layer

Question 28

bone cells; osteoblasts and osteoclasts

Answer 28

inner layer

Question 29

single layer of connective tissue that lines the internal surfaces of all cavities within bones such as the medullary cavity of the diaphysis and smaller cavities in spongy and compact bone

Answer 29

endosteum

Question 30

two processes of bone formation

Answer 30

intramembranous ossification and endochondral ossification

Question 31

locations in the membrane where intramembranous ossification begins

Answer 31

centers of ossification

Question 32

soft spots ; membrane covered spaces between developing skull bones that have not yet been ossified ; close by 2 years old

Answer 32

fontanels

Question 33

skull bones, part of the mandible, and diaphyses of clavicles (collarbones) develop by

Answer 33

intramembranous ossification

Question 34

based of the skull, part of mandible, epiphyses of clavicle, and remaining skeletal system develop through

Answer 34

endochondral ossification

Question 35

this type of bone grow by creating new cartilage in the epiphyseal plate

Answer 35

long bone

Question 36

bone that becomes old is replaced with new bone in a process called

Answer 36

bone remodeling

Question 37

living tissue that can repair itself if it is damaged

Answer 37

bone

Question 38

occurs when an open wound extends to the site of the fracture or protrudes through the skin

Answer 38

open fracture

Question 39

if skin is not perforated the fracture is called

Answer 39

closed fracture

Question 40

does not extend completely across the bone

Answer 40

incomplete fracture

Question 41

bone is broken into two fragments

Answer 41

complete fracture

Question 42

complete fracture in which the bone breaks into more than two pieces usually two major fragments and a smaller fragment

Answer 42

comminuted fracture

Question 43

one fragment is driven into the spongy portion of the other fragment

Answer 43

impacted fracture

Question 44

run parallel to the length of the bone

Answer 44

linear fracture

Question 45

right angles to the length of the bone

Answer 45

transverse fracture

Question 46

helical course around the bone

Answer 46

spiral fractures

Question 47

run obliquely in relation to the length of the bone

Answer 47

oblique fractures

Question 48

rough, toothed, broken ends

Answer 48

dentate fractures

Question 49

have breakage lines radiating from a central point

Answer 49

stellate fractures

Question 50

calcium homeostasis is regulated by three hormones

Answer 50

parathyroid hormone calcitriol calcitonin

Question 51

secreted by cells in the parathyroid gland ; essential for the maintenance of blood calcium levels within homeostatic levels

Answer 51

parathyroid hormones

Question 52

increases blood calcium levels ; steroid hormone derived from vitamin D

Answer 52

calcitriol

Question 53

secreted from C cells in the thyroid gland when blood calcium levels are too high

Answer 53

calcitonin

Question 54

average adult has how many bones

Answer 54

206 bones

Question 55

bones are segregated into two

Answer 55

axial skeleton appendicular skeleton

Question 56

how many bones does the skull have

Answer 56

22 bones

Question 57

how many bones does the appendicular skeleton have

Answer 57

126

Question 58

how many bones does the vertebral column have

Answer 58

26

Question 59

how many bone does the thoracic cage have

Answer 59

25 bones

Question 60

upper limbs, lower limbs, and two girdles

Answer 60

appendicular skeleton

Question 61

two girdles

Answer 61

pectoral and pelvic

Question 62

4 categories of bones based on their shape

Answer 62

long, short, flat, and irregular

Question 63

longer than they are wide

Answer 63

long bones

Question 64

wide as they are long ; help transfer force between long bones

Answer 64

short bones

Question 65

relatively thin, flattened shape

Answer 65

flat bones

Question 66

have shaped that do not fit readily into the three other categories ; specialized functions

Answer 66

irregular bones

Question 67

hole in a bone

Answer 67

foramen

Question 68

elongated hole ; tunnel like passage through a bone

Answer 68

canal or meatus

Question 69

depression in a bone

Answer 69

fossa

Question 70

rounded projection

Answer 70

tubercle or tuberosity

Question 71

sharp projection from a bone ; most are sites of muscle attachment

Answer 71

process

Question 72

smooth, rounded end of the bone, where it forms a joint with another bone is called

Answer 72

condyle

Question 73

bending movement that decreases the angle of the joint to bring the articulating bones closer together

Answer 73

flexion

Question 74

straightening movement that increases the angle of the joint

Answer 74

extension

Question 75

usually defined as the extension beyond 180 degrees

Answer 75

hyperextension

Question 76

movement of foot toward the plantar surface

Answer 76

plantar flexion

Question 77

movement of foot toward the shin

Answer 77

dorsiflexion

Question 78

movement away from the median or midsaggital plane

Answer 78

abduction

Question 79

movement toward the median plane

Answer 79

adduction

Question 80

palm is down

Answer 80

pronation

Question 81

palm faces up

Answer 81

supination

Question 82

turning the foot so plantar faces laterally

Answer 82

eversion

Question 83

turning foot so that plantar faces medially

Answer 83

inversion

Question 84

turning of a structure around its long axis

Answer 84

rotation

Question 85

occurs at freely movable joints such as the shoulder

Answer 85

circumduction

Question 86

glides anteriorly

Answer 86

protraction

Question 87

glides posteriorly

Answer 87

retraction