The Axial Skeleton

Front 1

How many bones are in the axial skeleton?
% of bones in the human body?

Back 1

80, 40%

Front 2

Components of the axial skeleton?

Back 2

Skull-8 cranial, 14 facial
Thoracic Cage- sternum, 24 ribs
Vertebral column-24 vert, sacrum, coccyx
6 auditory ossicles
hyoid bone

Front 3

Functions of axial Skeleton

Back 3

supports and protects the brain, spinal cord, organs
SA for attachment of muscles
that adjust the positions of the head, enck and trunk
perform respiratory movements
stabilize/position parts of the apendicular skeleton

Front 4

Characteristics of axial joints?

Back 4

limited movement
very strong
heavily reinforced by ligaments

Front 5

Skull has a total of how many bones? breakdown #s

Back 5

22.
8 cranium
14 associated with face

Front 6

how many bones associated with the skull?

Back 6

six auditory ossicles within temporal bones + hyoid

Front 7

8 cranial bones

Back 7

occipital
frontal
spenoid
ethmoid
parietal
temporal

Front 8

function of cranial bones

Back 8

enclose cranial cavity (fluid filled chamber that cushions and supports the brain)

Front 9

joint between occipital bone and first vertebrae vs. joint between other vertebrae and neck?

Back 9

1. stabilize position of the brain and spinal cord
2. wide range of head movements

Front 10

5 facial bones

Back 10

maxilla
lacrimal
nasal
zygomatic
mandible

Front 11

function of facial bones:

Back 11

attach muscle that control facial expressions
help in manipulating food

Front 12

3 deeper facial bones

Back 12

palatine bones
inferior nasal concha
vomer

Front 13

function of deeper facial bones

Back 13

separate oral and nasal cavities
increase SA of nasal cavities
form nasal septum, subdividint nasal cavity

Front 14

sinus

Back 14

air filled chambers in some bones of the skull

Front 15

function of sinus

Back 15

1. makes a bone lighter than it would be
2. mucous membrane lining produces mucus taht moistens and cleans the air around/in sinus

Front 16

joints/articulations
exception?

Back 16

formed when two bones interconnect.
exception: immovable joints between skull bones > suture

Front 17

suture

Back 17

bones tied together firmly with dense connective tissue

Front 18

4 major sutures

Back 18

1. lambdoid suture
2. coronal suture
3. sagittal suture
4. squamous suture

Front 19

where is the sqamous suture

Back 19

between temporal and parietal bones

Front 20

lambdoid suture characteristic

Back 20

one or more suture bones can be present along lambdoid suture

Front 21

what is calvaria, and formed by what bones?

Back 21

occipital, parietal, frontal bones form calvaria (skullcap)

Front 22

_______ bone forms most of the posterior and inferior cranial surface

Back 22

occipital

Front 23

articulations of occipital bone?

Back 23

1. parietal
2. temporal
3. sphenoid
4. first cervical vertebrae

Front 24

externial occipital crest

Back 24

begins at external occipital protuberance
where ligament that stabilizes the vertebrae of the neck attachs

Front 25

occipital condyles

Back 25

site of articulation between skull and first vertebrae

Front 26

__________ and ____________ are ridges that intersect the occipital crest. function?

Back 26

inferior and superior nuchal lines.
mark attachment sites of muscles and ligaments > stabilize articulations of occipital condyles, balance weight of head over vertebrae

Front 27

______ bones form part of superior and lateral cranial surface

Back 27

parietal

Front 28

frontal bone

Back 28

anterior cranium and roof of orbits (eye sockets)

mucous secretions of the frontal sinuses flush surfaces of nasal cavities

Front 29

forehead =

Back 29

frontal squama

Front 30

superior temporal line is

Back 30

continuous with superior temporal line of parietal bone

Front 31

supra-orbital margin

Back 31

thickening of the frontal bone that helps protect the eye

Front 32

lacrimal fossa

Back 32

on superior and lateral surface of orbit
shallow depression that marks the location of the lacrimal gland

Front 33

how do bones of the cranium form during developement?

Back 33

fusion of two separate centers of ossification

Front 34

is fusion complete by birth?

Back 34

no, the two frontal bones articulate along the frontal (metopic) suture.

Front 35

Function of temporal bones

Back 35

1. form part or both lateral walla of cranium/zygomatic
2. only articulations of mandible
3. surround and protect the sense organs of inner ear
4. attachment sites for muscles that close the jaws and move head

Front 36

squamous part of temporal bone

Back 36

convex, irregular surface, that borders squamous suture

Front 37

zygomatic arch

Back 37

cheekbone.
formed by zygomatic process of temporal bone and temporal process fo zygomatic bone = zygomatic arch

Front 38

mastoid process

Back 38

1. attachment for muscles that rotate/extend the head
2. contain mastoid air cells

Front 39

mastoiditis

Back 39

pathogens invade mastoid air cells > earaches, fever, swelling

Front 40

styloid process

Back 40

base of mastoid process
attached to ligaments that spoort hyoid bone and tendons of hyoid, tongue,pharynx

Front 41

petrous part of temporal bone

Back 41

encloses structures of inner ear : sense organs for hearing/balance

Front 42

auditory ossicles

Back 42

in tympanic cavity (middle ear)
three tiny bones on each side > transfer sound vibrations from typanic membrane > inner ear

Front 43

sphenoid

Back 43

1. unites cranial and facial bones
2. acts as cross brace that strengthens the sides of teh skull.
3. mucous secretions of sphenoidal sinus > help clean surfaces of nasal cavities

Front 44

body of sphenoid

Back 44

central axis

Front 45

sella turcica

Back 45

saddle shaped enclosure on superior surface of the body

Front 46

hypophyseal fossa

Back 46

depression within sella turcica
houses pituitary gland

Front 47

sphenoidal sinus

Back 47

large hole in the body

Front 48

lesser vs. greater wing
sphenoidal spine?

Back 48

lesser: horizontally anterior to ST
greater:laterally from body and forms part of the cranial floor
spenoidal spine > lies at posterior, lateral corner of greater wing

Front 49

pterygoid process

Back 49

vertical projections on either side of the body
forms pterygoid plates
site for muscles that move mandible and soft palate

Front 50

Ethmoid bone

Back 50

roof of nasal cavity
part of nasal septum and medial orbital wall

Front 51

ethmoid air cells

Back 51

mucous secretions from here flush surfaces of nasal cavities

Front 52

3 parts of ethmoid

Back 52

1. cribriform plate
2. paired lateral masses
3. perpendicular plate

Front 53

cribriform plate

Back 53

roof of nasal cavity

Front 54

crista galli

Back 54

bony ridge that projects above cribiform plate

Front 55

lateral masses contain __________ that consist of __________ ____ ______ that open into the nasal cavity on each side.

Back 55

ethmoid labyrinth > ethmoidal air cells

Front 56

what two bones are projections of the lateral masses?

Back 56

superior and middle nasal concha

Front 57

where are olfactory receptors located?

Back 57

1. epithelium that cover cribriform plate
2. medial surfaces of superior nasal concha
3. superior portion of perpendicular plate

Front 58

functon of nasal concha

Back 58

break up airflow in nasal cavity > creates swirls and turbulance causing
1. particles in the air aginst sticky mucus that covers wall of nasal cavity
2. turbulance slows air movement > warm, humidify, dust removal before air reaches respiratory tract
3. direct air toward superior portion of nasal cavity, adjacent to cribriform plate where olfactory receptors are located

Front 59

maxilla

Back 59

support uppoer teeth, inferior orbital rim, upper jaw, hard palate

largest facial bones

Front 60

maxillary sinus

Back 60

produce mucous secretions that flush inferior surfaces of nasal cavities

largest sinuses

Front 61

orbital rim

Back 61

protects eye and structures in orbit

Front 62

anterior nasal spine

Back 62

found at anterior portion of maxilla

attachment point for cartilage part of nasal septum

Front 63

alveolar process

Back 63

borders the mouth and supports upper teeth

Front 64

palatine process

Back 64

forms most of the hard palate
(bony roof of mouth)

Front 65

cleft palate

Back 65

disorder when maxilla fail to meet along midline of hard palate

Front 66

maxillary sinus

Back 66

lighten portion of maxilla above teeth

Front 67

nasolacrimal canal

Back 67

formed by maxilla and lacrimal bone
protect lacrimal sac an masolarimal duct
carries tears from orbit to nasal cavity

Front 68

inferior orbital fissure

Back 68

between maxilla and sphenoid

passage of cranial nerves and blood vessels

Front 69

palatine bones

Back 69

posterior portion of hard palate
L shaped

Front 70

parts of the palatine bone

Back 70

1. horizontal plate
2. perpendicular plate
3. orbital process

Front 71

nasal bones

Back 71

support superior portion of the bridge of the nose

connected to cartilage that support distal parts of nose

Front 72

external nares

Back 72

entrance of nasal cavity

Front 73

vomer

Back 73

inferior part of bony nasal septum

Front 74

nasal septum comprises of

Back 74

1. vomer
2. perpendicular plate of ethmoid

Front 75

inferior nasal concha

Back 75

creates turbulance in air passing through nasal cavity
increase epithelial SA
promote warming and humidification of inhaled air

Front 76

zygomatic bone

Back 76

rim and lateral wall of orbit
part of zygomatic arch

Front 77

zygomaticofacial foramen

Back 77

on anterior surface of each zygomatic bone
has sensory nerve that innervates the cheek

Front 78

lacrimal bones

Back 78

part of medial orbit wall
smallest facial bone

Front 79

lacrimal sinus is?
leads to?

Back 79

a groove on anterior lateral surface of lacrimal bone marks location of lacrimal sac.
> nasolacrimal canal

Front 80

mandible

Back 80

forms the lower jaw
articulate what mandibular fossa at temporal bone

Front 81

Mandibular:
body
alveolar process
mental protuberance
submandibular salivary gland
mylohyoid line

Back 81

> horizontal portion of bone
> alveolar process supports lower teeth
> attachment site for facial muscles
> depression on medial surface
> insertion of myohyoid muslce that supports floor of mouth

Front 82

Ramus of Mandible

Back 82

ascending part
beings at mandicular angle on either side

Front 83

what does the ramus of mandible have

Back 83

1. condylar process
2. coronoid process
3. mandibular notch

Front 84

condylar process

Back 84

articulates with temporal bone at the temporomandibular joint

Front 85

coronoid process

Back 85

insertion point for the temporalis muscle
powerful muscle that closes the jaw

Front 86

mandibular notch

Back 86

depression that separates the condylar and coronoid process

Front 87

hyoid bone

Back 87

supports larynx and attachment site for muscle of larynx, pharynx, and tongue

Front 88

stylohyoid ligaments

Back 88

connects the lesser horns to the styloid processes of the temporal bones

Front 89

body of hyoid

Back 89

attachment site for muscles of larynx, tongue, pharynx

Front 90

greater horn
vs.
lesser horn

Back 90

greater: supportthe larynx and attached to muscles that move the tongue
lesser: attached to stylohyoid ligaments
hyoid and larynx hang beneath the skull like a child's swing from the limb of a tree

Front 91

foramen magnum

Back 91

motor controll over several medulla oblongata provide neck and back muscles
vertebral arteries to brain, supporting membranes around CNS

Front 92

hypoglossal canal

Back 92

hypoglossal nerve control muscles of the tongue

Front 93

jugular foramen

Back 93

accessory nerve provide taste sensation

internal jugular vein > return blood from brain to heart

Front 94

supra-orbital foramen

Back 94

sensory branch of ophthalmic nerve > eyebrow, eyelid, frontal sinus

artery delivers blood to same region

Front 95

lacrimal sulcus, nasolacrimal canal

Back 95

lacrimal sac and tear duct drains blood to same region

Front 96

stylomastoid forament

Back 96

motor control of facial muscles

Front 97

carotid canal

Back 97

internal carotid artery supplies blood to brain

Front 98

external acoustic meatus

Back 98

air in meatus conducts sound to eardrim

Front 99

internal acoustic meatus

Back 99

vestibular nerve from sense organs for hearing and balance
facial nerve enters here, exits at stylomastoid foramen

IA artery: supplies blood to inner ear

Front 100

optic canal

Back 100

optic nerve> info from eye to brain

Front 101

superior orbital fissure

Back 101

oculomotor nerve
trochlear nerve
ophthalmic nerve : sensory info about eye and orbit

ophthalmic vein> returns blood from orbit

Front 102

forament rotundum

Back 102

maxillary branch of trigeminal nerve: sensation from the face

Front 103

foramen ovale

Back 103

mandibular branch of trigeminal nerve : muscles that move the lower jaw and provides sensory information

Front 104

foramen spinosum

Back 104

vessels to membrane around CNS

Front 105

foramen lacerum

Back 105

internal carotid artery leaving carotid canal
auditory tube
small vessels
hyaline cartilage

Front 106

inferior orbital fissure

Back 106

maxillary branch of trigeminal nerve

Front 107

olfactory foramina

Back 107

olfactory nerve provides sense of smell

Front 108

infra-orbital foramen

Back 108

infraorbital nerve
maxillary branch of trigeminal nerve from inferior orbital fissure to face

infraorbital artery

Front 109

mental foramen

Back 109

mental nerve > sensory branch of teh mandbular nerve
sensation from chin and lips

mental vessels to chin and lips

Front 110

mandibular foramen

Back 110

inferior alveolar nerve
sensory branch of mandibular nerve
provide sensation from gums, teeth

Front 111

zygomatic foramen

Back 111

zygomaticufacial nerve
sensory branch of maxillary nerve to cheeck

Front 112

orbital complex
1. what is it?
2. how many bones
3. what are the bones?
4. where do the foramina nd fissures penetrate?

Back 112

bony recesses that contain the eyes
7:
1. frontal
2. maxilla
3. lacrimal
4. ethmoid
5. sphenoid
6. palatine
7. zygomatic

penetrate sphenoid, or between sphenoid and maxilla

Front 113

Nasal complex
1. what is it?
2. how many bones
3. what are they?

Back 113

1. includes the bones that enclose the nasal cavities and paranasal sinuses (air filled chambers connected to the nasal cavities)

1. frontal
2. sphenoid
3. ethmoid
4. maxilla
5. lacrimal
6. ethmoid
7. inferior nasal concha
8. nasal bone

Front 114

bridge of the nose is supported by

Back 114

1. maxilla
2. nasal bone

Front 115

what bones make up the paranasal sinus?

Back 115

1. sphenoid
2. ethmoid
3. frontal bone
4. palatine bone
5. maxilla

Front 116

what is the function of the paranasal sinus?

Back 116

lighten the skul bones
provide extensive area of mucous epithelium > mucous secretions released into nasal cavities > swallowed or expelled by coughing

Front 117

what is involved in the formation of the skull? How does skull form?

Back 117

different centers of ossification fuse >producing small # of composite bones

Front 118

sphenoid began as ?

Back 118

14 separate ossification centers.

Front 119

is fusion completed at birth?

Back 119

no, you have
2 frontal bones
4 occipital bones
several sphenoid and temporal elements

Front 120

does cranial bone growth grow at the same rate as the brain?

Back 120

no, it fails to keep up

Front 121

how are cranial bones connected at birth? what are its characteristics

Back 121

by areas of fibrous connective tissue
1. flexible so skull can be distorted w/o damage, esp during delivery, change in head shape is necessary through birth canal

Front 122

fontanelles

Back 122

largest fibrous areas between the cranial bones

Front 123

What are the 4 types of fontanelles?

Back 123

1. anterior
2. occipital
3. sphenoidal
4. mastoid

Front 124

anterior fontanelle

Back 124

largest
intersection between frontal, sagittal, coronal sutures

"soft spot" on newborns
covers a major blood vessel
pulses as the heart beats
determines whether or not an infant is dehydrated via surface indentation

Front 125

occipital fontanelle

Back 125

junction between lambdoidal and sagittal sutures

Front 126

sphenoidal fontanelle

Back 126

joinctions between squamous suture and coronal suture

Front 127

mastoid fontanelle

Back 127

junction between squamous suture and lambdoid suture

Front 128

when do they disappear?

Back 128

O,S,M fontanelle disappears 2 months after birth
Anterior not until 2y

Front 129

Most significant skull growth period?

Back 129

before age 5.
at 5, the brain stops growing and cranial sutures develop

Front 130

craniostenosis

Back 130

unusual distortions of the skull due to premature closing of one or more fontanelles

Front 131

microcephaly

Back 131

undersized head b/c brain stops growing due to genetic or developmental abnormalities.

Front 132

vertebral column consists of how many bones? breakdown #s

Back 132

26
24 vertebral spine
sacrum, coccyx

Front 133

function of vertebrae

Back 133

column of support
transfer the weight of head, neck, and trunk
transfer weight of appendicular skeleton to the lower limbs
protect spinal cord
maintain upright body position
total length: 71 cm.

Front 134

four spinal curves

Back 134

1. cervical curve
2. thoracic curve
3. lumbar curve
4. sacral curve

Front 135

primary/accommodation curves

Back 135

thoracic and sacral curves (C) appear late in fetal development
accommodate thoracic and abdominopelvic viscera
present in vertebral column at birth

Front 136

secondary curves

Back 136

lumbar and cervical

Front 137

function of cervical and lumbar curve

Back 137

cervical: in infants, learning to balance weight of head on vertebrae of neck
lumbar: balance weight of trunk over lower limbs > develops with ability to stand

Front 138

lineage of weight transfer

Back 138

vertebral column > hips > lower limbs

Front 139

where does most of the body weight lie?

Back 139

anterior to the vertebral column

Front 140

function of various spinal curves

Back 140

align weight with body axis
may lead to discomfort at base of spinal column (late pregnancy)

Front 141

kyphosis
definition
caused by?

Back 141

humpback.
thoracic curvature exaggerated posterior

caused by:
1. osteoporosis + compression fractures affecting anterior portions of vertebral bodies
2. chronic contractions in muscles that insert on the vertebrae
3. abnormal vertebral growth

Front 142

lordosis
definition
caused by?

Back 142

bending backward
abdomen and buttocks protrude abnormally
cause:
anterior exaggeration of lumbar curvature
may be doing pregnancy
abdominal obesity or weakness in muscles of the abdominal wall

Front 143

scoliosis

Back 143

crookedness

abnormal lateral curvature of the spine
most common distortion of the spinal curvature
can occur in one or more vertebrae (movable only)

from developmental problems
muscular paralysis

generally in girls during adolescence

treat with metal rods/cables surgery. bracing prevents progression

Front 144

3 basic parts of the vertebrae

Back 144

1. body
2. vertebral arch
3. articular processes

Front 145

function of vertebral body

Back 145

transfer weight along axis of vertebral column
bodies of adjacent vertebrae are interconnected by ligaments, separated by intervertebral discs (pads of fibrous cartilage)

Front 146

vertebral arch
parts?

Back 146

posterior margin of each vertebral foramen
parts
1. pedicles (walls)
2. laminae (roof)

Front 147

vertebral canal

Back 147

formed by vertebral foramina of successive vertebrae
encloses spinal cord

Front 148

Processes

Back 148

1. spinous process: from vertebral lamina fusing to complete arch

2. transverse process: lamina to pedicles. sites of muscle attachment > articulate with ribs

3. superior and inferior articular process: arise between pedicles and laminae

Front 149

articular facet

Back 149

smooth concave surface

superior process have articular facets on dorsal surface.
inferior process have articular facets on ventral surface.

Front 150

intervertebral foramina

Back 150

gaps that separate pedicles of successive vertebrae.

passage of nerves from spinal cord.

Front 151

how many fused bones are in the sacrum vs. coccyx?
when are they completely fused by?

Back 151

5 vs. 3-5
age 25-30

Front 152

what pace of fusion can be variable depending on the individual?

Back 152

ossification of the distal coccygeal vertebrae not complete before puberty

Front 153

characteristics of cervical vertebrae

Back 153

1. smallest in vertebral column
2. from occipital bone to skull of thorax
3. large vertebral foramen
4. small body
5. contains most axons that connect brain with rest of the body
6. diameter of spinal cord decreases as you go down > so diameter of vertebral arch decreases too
7. tip of spinous process has prominent notch (bifid)
8. have transverse foramina
9. transverse process fuses to costal process
10. C3-C7 connections most flexible

Front 154

function of transverse process

Back 154

protect the vertebral arteries and veins: important vessels that service the brain

Front 155

whiplash

Back 155

dangerous partial or complete dislocation of cervical vertebrae> injury to muscles and ligaments and potential injury to spinal cord

Front 156

C1 =?
characteristics?

Back 156

atlas.
1. no spinous process
2. holds up head with the occipital condyles
3. permits nodding (yes)
4. lacks body
5. have large, round vertebral foramen bounded by anterior and posterior arches

Front 157

axis
characteristics?

Back 157

1. fused with atlas during dev'pt
2. dens (axis process)
3. pivot for rotation via transverse ligament between dens and atlas
4. fusion incomplete in children
> impact and shaking > dislocate dens > damage of spinal cord > can force dens into brain

Front 158

atlas or axis does "no" movement?

Back 158

axis

"earth rotates on its axis"

Front 159

vertebra prominens

characteristics?

Back 159

C7
between cervical and thoracic, opposite arches
SA for muscle attachment

Front 160

ligamentum nuchae

Back 160

elastic ligament begins at prominens to occipital crest > attach to spinal
processes of other cervical vertebrae

head upright >ligament maintain cervical curvature w/o muscular effort

bend neck forward: ligamental returns your head to upright position

Front 161

how many thoracic vertebrae?
chracteristics?

Back 161

12.
1. bigger
2. vertebral foramen smaller
3. each articulate with ribs via costal facets at the head of the rib

Front 162

compression fractures

Back 162

inferior thoracic and lumbar carry a lot of weight, transition between both is difficult to stabilize.

aka compression-dislocation fractures usually involve last thoracic and first two lumbar vertebrae.

Front 163

how do ribs articulate with vertebrae?

Back 163

4. T1-T8 articulate with 2 pairs of ribs, so have two costal facets (superior/inferior)
5. T9-T11, single costal facet on each side > articulate with 1 pair of ribs

Front 164

transverse costal facets

Back 164

T1-T10
for rib articulation
rib pairs contact vertebrae at 2 points:
1. costal facet
2. transverse costal facet

Front 165

lumbar vertebrae
how many?
characteristics?

Back 165

5
1. largest
2. body thickest
3. no costal facets
4. vertebral foramen is triangular
5. bear the most weight
6. attachment of lower back muscles to reinforce/adjust the lumbar curve

Front 166

sacrum
what is it?
function?

Back 166

5 bones fuse after puberty, completely fused by 25-30
protects:
1. reproductive
2. digestive
3. urinary organs
via paired articulations

attach axial skeleton to pelvic girdle
attach muscles that move thigh

Front 167

sacral canal

Back 167

between superior articular process of sacrum and last lumbar
extends length of sacrum
nerves and membranes from vertebral canal continue down here

Front 168

medial sacral crest

Back 168

ridge formed by fused spinous processes of sacral vertebrae

Front 169

sacral cornua

Back 169

laminae of fifth sacral vertebra fail to contact one another at midline

Front 170

sacral hiatus

Back 170

margins are sacral cornua
opening at inferior end of sacral canal
covered by connective tissue

Front 171

sacral foramina

Back 171

4 pairs on each side of median sacral crest

Front 172

lateral sacral crest

Back 172

on each side of the ridge that represents the fused transverse processes of the sacral vertebrae
provide SA for muscle attachment

Front 173

is sacrum straight or curved? Difference in men/women?

Back 173

curved, convex posterior surface
degree of curvature greater in men

Front 174

auricular usrface

Back 174

thickened, flattened area on lateral side
site of articulation with pelvic girdle

Front 175

sacral tuberosity

Back 175

roughened area between sacral crest and auricular surface.
attachment site of ligaments that stabilize sacroiliac joint

Front 176

apex vs base vs. sacral promontory, vs ala

Back 176

apex at bottom tip of sacrum, base vice versa
ala: wing (top)
sacral promontory: bulge at anterior top of base

Front 177

coccyx
# of bones

Back 177

3-5 usually 4 bones
begin fusing at age 26
attachment site for # of ligaments and muscle that constricts anal opening
1. first 2 have transverse process and unfused vertebral arches

Front 178

coccygeal cornua

Back 178

prominent lamina of first coccyx vertebrae
they curve to meet sacral cornua

do not fuse until late adulthood
elderly: coccyx may fuse with sacrum

Front 179

function of thoracic cage

Back 179

protects organs in chest
1. heart
2. lungs
3. thymus
sites for muscle attachment involved in
1. respiration
2. maintenance of vertebral column
3. movement of pectoral girdle and upper limbs
bony support of walls of thoracic cavity

Front 180

thoracic cavity consists of

Back 180

1. ribs
2. sternum
3. thoracic vertebrae

Front 181

ribs and sternum form

Back 181

rib cage, important for respiration

Front 182

ribs
description
where is it located
#

Back 182

flattened bones
originate on or between vertebrae and end in wall of thoracic cavity
12 pairs of ribs, 24 ribs

Front 183

ribs are connected to the sternum via

Back 183

costal cartilage

Front 184

how does the length and radius change as ribs go down?

Back 184

increase in length and radius of curvature.

Front 185

ribs 1-7
ribs 8-12
ribs 11/12

Back 185

true ribs
false ribs: dont directly connect to sternum
floating ribs: no connection with sternum: attached only to vertebrae and muscles of body wall

Front 186

vertebral end of rib articulates iwith vertebral column at
a ridge divides the articular surface of the head into

Back 186

head
superior and inferior articular facets

Front 187

tubercle

Back 187

small elevation that projects dorsally after the neck

Front 188

ribs 1-10 originate at costal facets on vertebrae

Back 188

T1-10

Front 189

Ribs 11 and 12 do not have ________________ or contact ____________.

Back 189

tubercular facets, transverse process of T11/12

Front 190

angle

Back 190

where tubercular body or shaft begins curving toward the sternum.

Front 191

internal rib surface is convex? concave?

Back 191

concave.

Front 192

costal groove

Back 192

along inferior border > path of nerves and blood vessels

Front 193

superficial surface convex/concave?
function

Back 193

convex
attachment site of muscle of pectoral girdle/trunk

Front 194

intercostal muscles
function
location

Back 194

move the ribs
attached at superior and inferior surfaces

Front 195

movements of ribs affect _______ and ________ of thoracic cage.
impact on volume?

Back 195

width and depth > increasing or decreasing volume
key in breathing

Front 196

rib fracture

Back 196

tightly bound by connective tissues> can heal w/o cast/splint
normally can bend and move to cushion shocks and absorb blows to a certain degree

compound fracture> send bone splinters into thoracic cavity > damage organs

Front 197

sternum description

Back 197

breastbone
flat bone in interior midline of thoracic wall

Front 198

3 components of sternum

Back 198

1. manubrium
2. body
3. xiphoid process

Front 199

manubrium
description & function

Back 199

broad, triangular
articulates with clavicles and cartilage of first pair of ribs
widest and most superior portion
only first pair of ribs is attached by cartilage here

Front 200

jugular notch

Back 200

between clavicular articulation
shallow indentation on superior surface of manubrium

Front 201

body

Back 201

costal cartilages from ribs 2-7attach here

Front 202

xiphoid process

Back 202

smallest part of sternum

muscular diaphragm and rectus abdominis muscles attach to the xiphoid process

Front 203

ossification of sternum begins when?
what process is last to ossify?

Back 203

begins at 6-10 ossification centers
before 25, not fused, so 4 separate bones
xiphoid process