Ch. 7 - Axial Skeleton

Question 1

Axial skeleton and homeostasis

Answer 1

The bones of the axial skeleton contribute to homeostasis by protecting many of the body’s organs

• The cranium surrounds the brain
• The vertebrae surround the spinal cord
• The ribs surround the heart and lungs

-Bones also support the storage and release of calcium, an important ion

Question 2

how many bones in the human skeleton?

Answer 2

206

Question 3

How many and what bones are in the axial skeleton?

Answer 3

80 bones;

skull bones, auditory ossicles, hyoid bone, ribs, sternum, vertebrae and sacrum

Question 4

How many and what bones are in the appendicular skeleton?

Answer 4

126 bones;

bones of the upper and lower extremities and the bones forming the girdles that connect the limbs to the axial skeleton

Question 5

Describe long bones.

Answer 5

greater in length than width.

Question 6

describe short bones.

Answer 6

cube shaped.

Question 7

describe flat bones

Answer 7

thin layers of parallel plates.

Question 8

describe irregular bones.

Answer 8

complex shape like vertebra

Question 9

describe sesamoid bones

Answer 9

shaped like a sesame seed.

Question 10

Bone Surface Markings- Depression and openings

Answer 10

• Allow the passage of soft tissues

- Form joints

Question 11

Bone Surface Markings- Processes

Answer 11

• Projections or outgrowths that form joints

- Serve as attachment points for ligaments and tendons

Question 12

Bone Surface Markings- Depression and openings— fissure

Answer 12

Narrow slit between bones for passage of blood vessels or nerves

Question 13

Bone Surface Markings- Depression and openings—foramen

Answer 13

Hole for passage of blood vessels, nerves or ligaments.

Question 14

Bone Surface Markings- Depression and openings—fossa

Answer 14

Shallow depression

Question 15

Bone Surface Markings- Depression and openings—meatus

Answer 15

tubelike opening

Question 16

Bone Surface Markings- Depression and openings—sulcus

Answer 16

Furrow on a bone for passage of blood vessel, nerve or tendon (see humerus, Fig. 8.4a)

Question 17

Bone Surface Markings- processes — condyle

Answer 17

Rounded projection with a smooth articular surface

Question 18

Bone Surface Markings- processes — facet

Answer 18

Smooth, flat, slightly concave articular surface

Question 19

Bone Surface Markings- processes — head

Answer 19

Usually rounded articular process supported on a neck

Question 20

Bone Surface Markings- processes — crest

Answer 20

Prominent ridge or elongated process

Question 21

Bone Surface Markings- processes — epicondyle

Answer 21

Usually roughened projection on a condyle

Question 22

Bone Surface Markings- processes — line

Answer 22

Long, narrow ridge or border (less prominent than a crest

Question 23

Bone Surface Markings- processes — spinous process

Answer 23

Sharp, slender projection; think about the spine vertebra

Question 24

Bone Surface Markings- processes — tronchanter

Answer 24

Very large projection found ONLY on the femur

Question 25

Bone Surface Markings- processes --- tubercle

Answer 25

Variably sized rounded projection

Question 26

Bone Surface Markings- processes --- tuberosity

Answer 26

Variably sized projection with rough, bumpy surface

Question 27

Sutural bones are...

Answer 27

small, extra bone plates located within the sutures of cranial bones; a suture is an immoveable joint. Found in the skull holding bones, such as the temporal and parietal, together

Question 28

Coronal suture

Answer 28

the junction between the frontal and parietal bones

Question 29

Squamous suture

Answer 29

the junction between the parietal and temporal bones

Question 30

Lambdoidal suture

Answer 30

the junction between the parietal and occipital bones

Question 31

Sagittal suture

Answer 31

the junction between the two parietal bones

Question 32

Fontanels

Answer 32

areas of a fetus/baby where unossified mesenchyme develop into dense connective tissue They close up through intramembranous ossification by 2 years of age

Question 33

The skull has how many bones?

Answer 33

The skull contains 22 bones, not including the 3 middle ear bones in both ears

Question 34

Skull- frontal bone

Answer 34

The frontal bone is a bone of the skull found in the forehead region. It is one of eight bones that form the cranium, or brain case. The frontal bone plays a vital role in supporting and protecting the delicate nervous tissue of the brain. It gives shape to the skull and supports several muscles of the head.

Question 35

Skull- Parietal and Temporal

Answer 35

One parietal bone is located on each side of the skull just behind the frontal bone. It is shaped like a curved plate and has four borders. Together, the parietal bones form the bulging sides and roof of the cranium. They are fused in the middle along the sagittal suture, and they meet the frontal bone along the coronal suture.

Question 36

Skull - occipital bone

Answer 36

The occipital bone joins the parietal bones along the lambdoidal suture. It forms the back of the skull and the base of the cranium. There is a large opening on its lower surface called the foramen magnum, through which nerve fibers from the brain pass and enter the vertebral canal to become part of the spinal cord.

Question 37

Skull - sphenoid bone

Answer 37

include: -lesser wing - sella turcica: +tuberculum sellae +hypophyseal fossa +dorsum sellae

Question 38

Skull - ethmoid bone

Answer 38

nose bone

Question 39

facial bones

Answer 39

Vomer, maxillae, and zygomatic bones

Question 40

facial bones - mandible

Answer 40

The mandible (lower jawbone) is the largest and strongest facial bone. Other than the middle ear bones (auditory ossicles), it is the only moveable skull bone.

Question 41

What are unique features of the skull?

Answer 41

Paranasal sinuses - mucous membrane-lined cavities in the frontal, maxillary, sphenoid and ethmoid bones - -Used as resonating chambers to enhance the voice - -Increase the surface area of the nasal mucosa and help to moisten it as well

Question 42

Sinusitis

Answer 42

As the sinuses directly continue from the nasal cavity, infections of the upper respiratory tract, such as the flu, or rhinitis, can easily spread into the sinus cavities, leading to a condition called sinusitis [2]. Characteristic symptoms include a sinus headache, facial pain or tenderness, and feeling of a stuffy nose [16]. Most commonly affecting the maxillary sinuses [17], inflammation or infection in this area may cause pain in the maxillary teeth as both are innervated by the maxillary nerve [9]. Any blockage in a sinus passage may cause mucus to accumulate, also leading to bacterial or viral infections [18].

Question 43

Hyoid bone (adam's apple)

Answer 43

Does not articulate with any other bone | Supports the tongue and provides an attachment site for some muscles of the neck and pharynx

Question 44

Vertebral Column- how many vertebrae?

Answer 44

Also known as the spinal column, backbone or spine | Composed of 26 vertebrae

Question 45

Vertebral Column- divided into how many regions?

Answer 45

divided into 5 regions

Question 46

Vertebral Column- function?

Answer 46

Protects the spinal cord

Question 47

Curves of the Vertebral column:

Answer 47

1. Cervical curve - 7 2. Thoracic curve - 12 3. lumbar curve - 5 4. sacral curve - 5 fused sacral vertebrae

Question 48

Where are intervertebral disc located?

Answer 48

Located between the bodies of the vertebrae from the second cervical to the sacrum

Question 49

what are intervertebral discs composed of?

Answer 49

Composed of an outer ring of fibrocartilage (annulus fibrosus) and an inner, soft nucleus (nucleus pulposus) with a layer of hyaline cartilage on the top and bottom of each disc

Question 50

what are intervertebral discs' function?

Answer 50

Absorb shock and separate the vertebrae from one another

Question 51

Function of the thoracic vertebrae? structure?

Answer 51

Support the ribs and have special structures for rib head and tubercle attachment. LOOKS LIKE A GIRAFFE

Question 52

Function of the lumbar vertebrae? Structure?

Answer 52

The largest and strongest vertebrae No special structures that are specifically associated with these vertebrae. LOOKS LIKE A MOOSE.

Question 53

Function of the cervical vertebra?

Answer 53

support the skull. LOOKS SMALL AND BUG LIKE

Question 54

Structure of the sacrum.

Answer 54

The triangular-shaped sacrum is part of the pelvic girdle and is composed of 5 vertebrae that fuse

Question 55

structure of the coccyx.

Answer 55

The coccyx is much smaller than the sacrum but is also triangular in shape and is composed of 4 vertebrae that fuse.

Question 56

What is the thorax and what is it composed of?

Answer 56

The thorax is the entire chest region. The bones that compose the thoracic cage are the sternum, ribs and costal cartilages

Question 57

What is the sternum composed of?

Answer 57

part of the thorax. Composed of 3 segments: 1. The upper manubrium 2. The middle body 3. The lower xiphoid process

Question 58

What bone does the sternum articulate with?

Answer 58

The sternum articulates with the clavicles and the costal cartilages.

Question 59

Thorax: RIBS - how many are there?

Answer 59

12 pairs

Question 60

Thorax: RIBS - function?

Answer 60

Provide structural support to the thoracic cavity

Question 61

Thorax: RIBS - true (vertebrosternal) ribs?

Answer 61

True (vertebrosternal) ribs – first 7 pairs; their cartilage is directly connected to the sternum

Question 62

Thorax: RIBS - false (vertebrochondral) ribs?

Answer 62

False (vertebrochondral) ribs – next 5 pairs; cartilage is indirectly connected to the sternum

Question 63

Thorax: RIBS - floating (vertebral) ribs?

Answer 63

Floating (vertebral) ribs – last 2 pairs; these are not connected to the sternum

Question 64

Disorders: what is a herniated disc?

Answer 64

In the vertebral column, a herniated disc may occur due to trauma or sometimes is simply associated with aging

Question 65

Disorders: scoliosis?

Answer 65

(increased lateral curvature)

Question 66

Disorders: kyphosis?

Answer 66

(increased thoracic curve-bent forward)

Question 67

Disorders: Lordosis?

Answer 67

(increased lumbar curve-bent backwards)

Question 68

Disorders: spina bifida?

Answer 68

Spina bifida is a congenital defect of the vertebral column where the laminae do not develop normally The degrees of this deformity vary from minor (spina bifida occulta) to severe (spina bifida with meningomyelocele)