Anatomy Chapter 6

Front 1

Axial skeleton

Back 1

consists of the bones of the skull, thorax, and vertebral column. These elements form the longitudinal axis of the body

Front 2

Characteristics of axial skeleton

Back 2

-framework that supports and protects organs in the ventral body cavities
-houses special sense organs
-provides surface area for the attachment of muscles
-joints of axial skeleton permit limited movement, but they are very strong and often heavily reinforced with ligaments

Front 3

How many bones are in the axial skeleton?

Back 3

22 bones
(8 cranium and 14 facial bones)

Front 4

Bones of the cranium

Back 4

Frontal, Parietal (2), Occipital, Temporal (2), Sphenoid, Ethmoid

Front 5

Lambdoid suture

Back 5

the lambdoid suture arches across the posterior surface of the skull, separating the occipital bone from the parietal bones

Front 6

Sagittal suture

Back 6

the sagittal suture begins at the superior midline of the lambdoid suture and extends anteriorly between the parietal bones to the coronal suture

Front 7

Coronal suture

Back 7

anteriorly, the sagittal suture ends when it intersects the coronal suture. The coronal suture crosses the superior surface of the skull, separating the frontal bone from the more posterior parietal bones

Front 8

Squamous suture

Back 8

a squamous suture on each side of the skull marks the boundaries between the temporal bone and the parietal bone

Front 9

Frontonasal suture

Back 9

the frontonasal suture is the boundary between the superior aspects of the two nasal bones and the frontal bone

Front 10

Maxillary bones

Back 10

-largest facial bones
-together form upper jaw
-articulates with all other facial bones except the mandible

Front 11

Palatine bones

Back 11

-small L-shaped bones
-articulate with the maxillae to form the posterior portions of the hard palate

Front 12

Nasal bones

Back 12

articulate with frontal bones at the midline of the face at the frontonasal suture

Front 13

Zygomatic bones

Back 13

cheek bones

Front 14

Lacrimal bones

Back 14

-smallest bones of the skull
-enclose tear ducts
-corner of orbits

Front 15

Vomer

Back 15

-form inferior portion of nasal septum

Front 16

Mandible-

Back 16

forms entire lower jaw

Front 17

Inferior nasal conchae

Back 17

-paired scroll like bones
-located on each side of nasal septum, attached to the lateral wall of the nasal cavity

Front 18

Facial bones of the skull

Back 18

-Maxillary (2)
-Palatine (2)
-Zygomatic (2)
-Lacrimal (2)
-Nasal (2)
-Vomer
-Inferior Nasal conchae (2)
-Mandible

Front 19

Fontanel

Back 19

a relatively soft, flexible, fibrous region between two flat bones in the developing skull

Front 20

Primary curvature

Back 20

-thoracic and sacral curves
-because they appear late in fetal development

Front 21

Secondary curvature

Back 21

-lumbar and cervical curves
-help shift trunk weight over the legs as the child begins to stand

Front 22

How many bones are in the vertebral column?

Back 22

26 bones

Front 23

Regions of the vertebral column

Back 23

Cervical, Thoracic, Lumbar, Sacral, Coccygeal

Front 24

Spinal Curvatures

Back 24

Cervical, thoracic, lumbar, pelvic

Front 25

How many curvatures are present in an infant?

Back 25

Two, thoracic and sacral

Front 26

Body of vertebra

Back 26

Centrum
part of vertebra that transfers weight along the axis of the vertebral column
--each vertebra articulates with neighboring vertebrae, the bodies are interconnected by ligaments and separated by intervertebral discs

Front 27

What comprises the vertebral arch?

Back 27

Vertebral foramen, laminae, pedicles

Front 28

Vertebral foramen

Back 28

In a typical vertebra, the vertebral foramen is the foramen formed by the anterior segment (the body), and the posterior part, the vertebral arch.

Front 29

Laminae

Back 29

The laminæ are two broad plates, extending dorsally and medially from the pedicles, fusing to complete the roof of the vertebral arch

Front 30

Spinous process

Back 30

The spinous process of a vertebra is directed backward and downward from the junction of the laminae (in humans), and serves for the attachment of muscles and ligaments

Front 31

Intervertebral foramina

Back 31

gaps between pedicles of successive vertebrae.
--permit the passage of nerves running to or from the enclosed spinal cord

Front 32

Vertebral canal

Back 32

vertebral arches of the vertebral column together form the vertebral canal, a space that encloses the spinal cord

Front 33

Atlas

Back 33

C1
-holds up the head
-articulates with occipital condyles of skull at the superior articular facet of the superior articular process
-lacks body
-during development, atlas fuses with the axis--body becomes the dens

Front 34

Axis

Back 34

C2
-It forms the pivot upon which the first cervical vertebra (the atlas), which carries the head, rotates.

The most distinctive characteristic of this bone is the strong odontoid process ("dens") which rises perpendicularly from the upper surface of the body.

Front 35

Vertebra prominens

Back 35

C7
-interface between cervical curve and thoracic curve
-long, slender spinous process that ends in a broad tubercle
--->effected by whiplash

Front 36

Cervical vertebrae

Back 36

-7
-smallest of vertebrae
-body is small compared with the size of the triangular vertebral foramen
-has transverse foramen
-supports skull, stabilizes relative positions of brain and spinal cord, allows controlled head movement

Front 37

Thoracic vertebrae

Back 37

-12
-heart shaped body, more massive than that of cervical
-vertebral foramen is smaller
-all but two have facets for rib articulations
-supports weight of head,neck, upper limbs, organs of thoacic cavity
-articulates with ribs to allow changes in volume of thoracic cage

Front 38

Lumbar vertebrae

Back 38

-5
-most massive vertebral body
-smallest vertebral foramen
-supports weight of head, neck, upper limbs, organs of thoacic and abdominal cavities

Front 39

sacrum

Back 39

only one bone, formed through fusion of 5 bones

Front 40

Auricular surface

Back 40

place for articulation between sarcrum and pelvic girdle

Front 41

Coccyx

Back 41

The coccyx provides an attachment site for a number of ligaments and for a muscle that constricts the anal opening

result of the fusion of individual vertebrae

Front 42

Functions of throacic cage

Back 42

-protects the heart, lungs, thymus, and other structures in the thoracic cavity
-serves as attachment point for muscles involved with
1. respiration
2. position of vertebral column
3. movements of pectoral girdle and upper limbs

Front 43

How many ribs?

Back 43

12 pairs

Front 44

vertebrosternal

Back 44

true ribs
ribs 1-7
at the anterior body wall the true ribs are connected to the sternum by separate costal cartilages

Front 45

vertebrochondral

Back 45

false ribs
ribs 8-12
do not attach directly to the sternum, costal cartilages of ribs 8-10 fuse together before reaching the sternum. ribs 10-12 have no connection to the sternum

Front 46

floating ribs

Back 46

ribs 10-12
no connection to the sternum

Front 47

costal groove

Back 47

groove in the ribs where blood vessels and nerves travel

Front 48

Manubrium

Back 48

articulates with the clavicles of the appendicular skeleton and the costal cartilages of the first pair of ribs

only bony connection between upper limb and axial skeleton

Front 49

Body of sternum

Back 49

attaches ribs 2-7
ribs 8-10 are also attached to the body, but by a single pair of cartilages shared with rib pair 7

Front 50

xiphoid process

Back 50

smallest part of the sternum
-diaphragm and rectus abdominis muscle attach to xiphoid process
-breaks off really easily, can lacerate the liver during CPR

Front 51

Jugular notch

Back 51

shallow indentation on the superior surface of the manubrium, located between the clavicular articulations