Exercise 9: The Axial Skeleton

Front 1

What are the 3 main components of the axial skeleton?

Back 1

the skull, the vertebral column, and the thoracic cage.

Hint 1

Front 2

The skull is composed of 2 sets of bones. What are they?

Back 2

cranial and facial bones

Hint 2

Front 3

How many cranial bones are there?

Back 3

8

Hint 3

Front 4

How many facial bones are there?

Back 4

14

Hint 4

Front 5

What are the cranial vault (calvaria) bones of the human skull?

Back 5

frontal, parietal, and temporal bones

Front 6

What are the cranial floor (base) bones of the human skull?

Back 6

anterior cranial fossae, middle cranial fuss, posterior cranial fuss, occipital, sphenoid, ethmoid

Front 7

What are the two major areas of the cranium?

Back 7

cranial vault (calvaria) and cranial base

Front 8

___________ forms the superior, lateral and posterior walls of the skull.

Back 8

The cranial vault, or calvaria

Hint 8

Front 9

___________ forms the skull bottom.

Back 9

The cranial base

Hint 9

Front 10

_______ forms the forehead, superior part of the orbit, and the floor of the anterior cranial fossae.

Back 10

Frontal bone

Hint 10

Front 11

________ forms the superior and lateral aspects of the skull.

Back 11

Parietal bone

Hint 11

Front 12

__________ forms the inferolateral ( both inferior and lateral...below and to one side) of the skull and contribute to the middle cranial fossa.

Back 12

Temporal bone

Hint 12

Front 13

_______ forms the posterior aspect and most of the base of the skull.

Back 13

Occipital bone

Hint 13

Front 14

Bat-shaped bone that is described as the keystone bone of the cranium because it articulates with all other cranial bones.

Back 14

Sphenoid bones

Hint 14

Front 15

Contribues to the anterior cranial fossa; forms part of the nasal septum and the nasal cavity; contributes to the medial wall of the orbit.

Back 15

Ethmoid bones

Hint 15

Front 16

Where are the 4 largest sutures of the skull located?

Back 16

Where the parietal bones articulate (form a joint) with each other and where the parietal bones articulate with other cranial bones

Hint 16

Front 17

Occurs where the left and right parietal bones meet superiorly in the midline of the cranium

Back 17

Sagittal suture

Hint 17

Front 18

Running in the frontal plane, occurs anteriorly where the parietal bones meet the frontal bone

Back 18

Coronal suture

Hint 18

Front 19

Occurs where each parietal bone meets the temporal bone, on each lateral aspect of the skull

Back 19

Squamous suture

Hint 19

Front 20

Occurs where the parietal bones meet the occipital bone posteriosly

Back 20

Lambdoid suture

Hint 20

Front 21

Which cranial landmark do the two supraorbital foramen (notch) belong to?

Back 21

Frontal

Hint 21

Front 22

Opening above each orbit allowing blood vessels and nerves to pass

Back 22

Supraorbital foramen

Hint 22

Front 23

Which cranial landmark do these belong to? - zygomatic process, mandibular fossa, external auditory meatus, styloid process, mastoid process, and internal acoustic meatus

Back 23

Temporal

Hint 23

Front 24

A bridgelike projection that articulates with the zygomatic bone to form the zygomatic arch

Back 24

Zygomatic process

Hint 24

Front 25

Located on the inferior surface of the zygomatic process; receives the condylar process of the mandible to form the temporomandibular joint

Back 25

Mandibular fossa

Hint 25

Front 26

What is the landmark?

Back 26

External auditory meatus or external acoustic meatus

Hint 26

Canal leading to the middle ear and eardrum

Front 27

Needlelike projection that serves as an attachment point for ligaments and muscles of the neck

Back 27

Styloid process

Hint 27

Front 28

Located posterior to the external acoustic meatus; serves as an attachment point for neck muscles

Back 28

Mastoid process

Hint 28

Front 29

What is this landmark?

Back 29

Internal acoustic meatus

Hint 29

OPPOSITE of external acoustic meatus

Front 30

Which landmark do these belong to? - foramen magnum and occipital condyles

Back 30

Occipital

Hint 30

Front 31

Large opening in the base of the bone, which allows the spinal cord to join with the brain stem

Back 31

Foramen magnum

Hint 31

Front 32

Rounded projections lateral to the foramen magnum that articulate with the first cervical vertebra (atlas)

Back 32

Occipital condyles

Hint 32

Front 33

Which cranial landmark do these belong to? -greater wings, sella truck, lesser wings, and optic canals?

Back 33

Sphenoid

Hint 33

Front 34

Project laterally from the sphenoid body, forming arts of the middle cranial fossa and the orbits

Back 34

Greater wings

Hint 34

Front 35

Form part of the floor of the anterior cranial fossa and part of the orbit

Back 35

Lesser wings

Hint 35

Front 36

"Turkish saddle" located on the s superior surface of the body; the seat of the saddle, called the hypophyseal fossa, holds the pituitary gland

Back 36

Sella turcica

Hint 36

Front 37

Openings in the base of the lesser wings, cranial nerve II (optic nerve) passes through to serve the eye

Back 37

Optic canals

Hint 37

Front 38

Which cranial landmark do these belong to? - superior and middle nasal conchae (turbinates)

Back 38

Ethmoid

Hint 38

Front 39

Extend medially from the lateral masses; act as turbinates to improve airflow through the nasal cavity

Back 39

Superior and middle nasal conchae (turbinates)

Hint 39

Front 40

Of the 14 bones composing the face, how many are paired?

Back 40

12

Hint 40

Less than 15 but more than 10

Front 41

Of the 14 facial bones, only the ________ and _______ are single bones.

Back 41

mandible, vomer

Front 42

Which facial bone landmarks do these belong to? - body, rams, mandibular condyle, coronoid process, mental foramen, mandibular foramen, and mandibular symphysis?

Back 42

Mandible

Hint 42

Front 43

Horizontal portion that forms the chin

Back 43

Body

Hint 43

Front 44

Vertical extension of the body

Back 44

Ramus

Hint 44

Front 45

Which landmark of the mandible is this?

Back 45

Mandibular condyle

Front 46

"Crown-shaped" portion of the rams for muscle attachment

Back 46

Coronoid processes

Hint 46

Front 47

Paired openings on the body (lateral to the midline); transmit blood vessels and nerves to the lower lip and skin of the chin

Back 47

Mental foramen

Hint 47

Front 48

Located on the medial surface of each ramus; passageway for the nerved involved in tooth sensation. (Dentists inject anesthetic into this foramen before working on the lower teeth.)

Back 48

Mandibular foramen

Hint 48

Front 49

Which landmark of the mandible is this?

Back 49

Mandibular symphysis

Front 50

Which facial bone landmark does the infraorbital foramen belong to?

Back 50

Maxilla

Hint 50

Front 51

Opening under the orbit that forms a passageway for the infraorbital artery and nerve

Back 51

Infraorbital foramen

Hint 51

Front 52

Forms the posterior hard palate, a small part of the nasal cavity, and part of the orbit

Back 52

palatine bone

Hint 52

Front 53

Commonly called the cheekbones; each for part of the lateral orbit

Back 53

Zygomatic bones

Hint 53

Front 54

Each forms part of the medial orbit in between the maxilla and ethmoid bone

Back 54

Lacrimal bones

Hint 54

Front 55

Small rectangular bones forming the bridge of the nose

Back 55

Nasal bones

Hint 55

Front 56

Thin, blade-shaped bone that forms the inferior nasal septum

Back 56

Vomer

Hint 56

Front 57

Interior turbinate; each forms part of the lateral walls of the nasal cavities; improves the airflow through the nasal cavity

Back 57

Interior nasal conchae

Hint 57

Front 58

What bone is located in the throat above the larynx and serves as a point of attachment for many tongue and neck muscles?

Back 58

Hyoid bone

Hint 58

Front 59

What are the landmarks of hyoid bone?

Back 59

greater horn, lesser horn, and body

Hint 59

Front 60

What are the 4 skull bones of paranasal sinuses?

Back 60

maxillary, sphenoid, ethmoid, and frontal

Hint 60

Front 61

What features do all vertebrae have in common?

Back 61

Body (centrum), vertebral arch, vertebral (spinal) foramen, transverse processes, spinous process, superior and inferior articular process, and intervertebral foramina

Hint 61

Front 62

The vertebral column is divided into ___ sections with ___ composite bones.

Back 62

3,2

Hint 62

Front 63

What portion of the vertebral column do the 7 cervical vertebrae form?

Back 63

the neck portion

Hint 63

Front 64

What are the first two cervical vertebrae that are highly modified to perform special functions?

Back 64

atlas and axis

Hint 64

Front 65

The ___ (C1) lacks a body; enables you to nod "yes"

Back 65

atlas

Hint 65

Front 66

The ___ (C2) acts as pivot (central point or pin) for the rotation of the atlas (and the skull) above.

Back 66

axis

Hint 66

Front 67

The axis of the cervical vertebrae bears a large vertical process called the _____ that serves as the pivot point.

Back 67

dens

Hint 67

Front 68

What function of the body does the articulation between C1 and C2 provide?

Back 68

It allows you to rotate your head from side to side to indicate "no"

Hint 68

It does the opposite of allowing you to nod your head "yes".

Front 69

How many cervical vertebrae are there?

Back 69

7

Hint 69

Front 70

How many thoracic vertebrae are there?

Back 70

12

Hint 70

Front 71

The thoracic vertebrae are characterized by...

Back 71

long, sharp spinous processes and rib facets

Hint 71

Front 72

How many lumbar vertebrae are there?

Back 72

5

Hint 72

Front 73

The lumbar vertebrae are characterized by....

Back 73

short, blunt spinous process and a large body

Hint 73

Front 74

The _____ is a composite bone formed from the fusion of 5 vertebrae.

Back 74

sacrum

Hint 74

Front 75

The ______ is a composite bone formed from the fusion of _ - _ small irregularly shaped vertebrae.

Back 75

coccyx, 3-5

Hint 75

Front 76

What are the abnormal spinal curvatures?

Back 76

scoliosis, kyphosis, lordosis

Hint 76

Front 77

What does the thoracic cage do?

Back 77

The thoracic cage encloses and protects the heart and lungs.

Hint 77

t

Front 78

What does the thoracic cage consist of?

Back 78

The thoracic cage consists of the bony thorax, which is composed of the sternum, ribs, and thoracic vertebrae, plus the costal cartilage.

Hint 78

Front 79

What does a sternum consist of?

Back 79

jugular notch, manubrium, sternal angle, body, typhoid process

Hint 79

Front 80

How many pairs of ribs are there?

Back 80

12

Hint 80

Front 81

What do the ribs consist of?

Back 81

true ribs (1-7), false ribs (8-12), and floating ribs (11 & 12)

Hint 81

Front 82

What does the skull consist of?

Back 82

fontanelles, frontal bone, occipital bone, parietal bone, temporal bone, frontal suture.

Hint 82

Front 83

Skull bones are incompletely formed at birth and connected by fibrous membranes called _______________.

Back 83

fontanelles

Hint 83

Front 84

What is the function of the fontanelles?

Back 84

The fontanelles allow the fetal skull to be compressed slightly during birth and also allow for brain growth in the fetus and infant. They ossify (become bone) as the infant ages.

Front 85

What are the landmarks of fontanelles?

Back 85

anterior, posterior, sphenoidal, and mastoid

Hint 85

Front 86

The fetal skeleton is composed of ______ bones, while an adult skeleton has _____ bones.

Back 86

275, 206

Front 87

Why does a fetal skeleton have less number bones than an adult skeleton?

Back 87

Because some bones have not yet fused together in a fetus