Chapter 7 The Skeleton review questions

1. What does skeleton mean in Greek?

"Dried up body" or "mummy".

How many false?

5 rib pairs.

Thigh

61. The thigh is the region between the hip and knee. It has one bone, the femur.

Leg

64. The leg is the region between the knee and ankle. It has two bones, the tibia and fibula.

17. Temporal bones

Articulate with the parietal bones and form the inferolateral aspects of the skull and parts of the cranial floor. The temporal bone is characterized by the mandibular fossa and the external auditory meatus which house the ear.

14. Fontal bone

Articulates posteriorly with the parietal bones via the coronal suture, extends forward to the supraorbital margins, and extends posteriorly to form the superior wall of the orbits and most of the anterior cranial fossa.

16. Occipital bone

Articulates with the parietal, temporal, and sphenoid bones, forming most of the posterior wall and base of the skull.

4. What are the two divisions of the skeleton?

Axial and appendicular portions.

2. What are the 4 main things the skeleton composed of?

Bones, cartilages, joints, and ligaments.

Name the five major divisions and give the number of bone in each:

Cervical (7), thoracic (12), lumbar (5), sacrum (5), Coccyx (4)

• Which sections curve concave?

Cervical and lumbar.

When so the membranes of the skull begin to ossify?

Membrane bones of the skull begin to ossify late in the second month of development.

11. What is the main function of the 85 named openings in the skull?

Provide passageways for the spinal cord, the major blood vessels serving the brain, and the 12 pairs of cranial nerves, which transmit impulses to and from the brain.

18. Sphenoid bone

Spans the width of the middle cranial fossa, and articulates with all other cranial bones.

What is the function of these ligaments?

Support, prevents hyperextension and hyperflexion of the spine (bending to far back or too sharply forward).

Name the seven tarsal bones:

Talus, calcaneus, lateral cuboid, medial navicular, and the anterior medial. intermidiate, and lateral cuneiform bones.

23. Zygomatic bones

articulate with temporal, frontal, and maxillary bones, and form the prominences of the cheeks and parts of the inferolateral margins of the orbits.

55. Radius

articulates with the humerus and the ulna medially at the proximal end via a flattened head. It articulates with the carpals of the wrist and the ulna medially at the distal end.

orbits

bony cavities that contain the eyes, muscles that move the eyes, and tear-producing glands. • They consist of the frontal, sphenoid, zygomatic, maxilla, palatine, lacrimal, and ethmoid bones.

26. Palatine bones

consist of bony plates that complete the posterior portion of the hard palate, form part of the posterolateral walls of the nasal cavity, and small parts of the orbits.

68. Metatarsus - or metatarsals

consists of five small, long bones called metatarsal bones which number 1 to 5 beginning on the medial side of the foot.

The Pectoral (Shoulder) Girdle

consists of the clavicle, which joins the sternum anteriorly, and the scapula, which is attached to the posterior thorax and vertebrae via muscular attachments. 50. The pectoral girdles are very light and have a high degree of mobility due to the openness of the shoulder joint and the free movement of the scapula across the thorax.

Clavicles (collarbones)

extend horizontally across the thorax, articulating medially with the sternum, and laterally with the scapula, bracing the arms and scapulae laterally.

At birth, skull bones are connected by?

fontanels, unossified remnants of fibrous membranes.

Pubic bones

form the anterior portion of the coxae. They are joined by a fibrocartilage disc, forming the midline pubic symphysis.

24. Nasal bones

form the bridge of the nose, and articulate with the frontal, maxillary, and ethmoid bones, along with the cartilages that form most of the skeleton of the external nose.

22. Maxillary bones

form the upper jaw and central portion of the face, articulating with all other facial bones except the mandible.

a. The sides of the thoracic cage are?

formed pairs of ribs that attach posteriorly to the thoracic vertebrae and curve inferiorly toward the anterior body surface.

54. Ulna

forms the elbow joint with the humerus. It articulates with the radius laterally at the proximal end, and articulates with the bones of the wrist via a cartilage disc at the distal end.

42. Lumbar vertebrae

large vertebrae that have kidney-shaped bodies, a triangular vertebral foramen, short, thick pedicles and laminae, and short, flat, hatchet-shaped spinous processes.

46. Sternum (breastbone)

lies in the anterior midline of the thorax, and is a flat bone resulting from the fusion of three bones:

27. Vomer

lies in the nasal cavity, where it forms part of the nasal septum.

Hyoid bone

lies inferior to the mandible in the anterior neck. It is the only bone that does not articulate directly with any other bone.

25. Lacrimal bones

located in the medial wall of the orbits, and articulate with the frontal, ethmoid, and maxillary bones.

70. Arches of the foot

maintained by interlocking foot bones, ligaments, and the pull of tendons during muscle activity.

Intervertebral foramen.

notches on the superior and inferior borders of the pedicals.

56. Carpus (wrist)

or carpal bones consists of eight short bones arranged in two irregular rows of four bones each:

57. Metacarpus (palm)

or metacarpals consist of five small, long bones numbering one through five from thumb to little finger. It articulates with the carpals proximally, and the proximal phalanges distally.

3. What percent is the skeleton in body mass?

20%

Vertebral Column

31. The vertebral column consists of 26 irregular bones, forming a flexible, curved structure extending from the skull to the pelvis.

47. How my pairs of ribs are there?

12

How many are there?

2 pairs.

Demifacet

2 small faucets on the thoracic vertebrae, one at the superior edge and the other at the inferior edge. The demifacets recieve the heads of the ribs.

Structure of Vertebrae

37. Each vertebra consists of an anterior body and a posterior vertebral arch that, together with the body, form the vertebral foramen.

Changes in cranial-facial proportions and fusion of bones

71. At birth, the cranium is much larger than the face, and several bones are still unfused. 72. By nine months, the cranium is half the adult size due to rapid brain growth. 73. By age 8-9, the cranium has reached almost adult proportions. 74. Between ages 6-13, the jaws, cheekbones, and nose become more prominent, due to expansion of the nose, paranasal sinuses, and development of permanent teeth.

Curvatures of the Spine occur?

75. The primary curvatures (thoracic and sacral curvatures) are convex posteriorly and are present at birth. 76. The secondary curvatures (cervical and lumbar curvatures) are convex anteriorly and are associated with the child's development. 77. The secondary curvatures result from reshaping the intervertebral discs.

Changes in body height and proportion occur throughout childhood

78. At birth, the head and trunk are roughly 1 1/2 times the length of the lower limbs. 79. The lower limbs grow more rapidly than the trunk, and by age 10, the head and trunk are about the same length as the lower limbs. 80. During puberty, the female pelvis widens and the male skeleton becomes more robust.

Effects of old age on the skeleton

81. The intervertebral discs become thinner, less hydrated, and less elastic. 82. The thorax becomes more rigid, due to calcification of the costal cartilages. 83. All bones lose bone mass.

36. Intervertebral discs

A cushionlike pad composed of 2 parts - The inner gelatinous nucleus pulposus and the anulus fibrosus.

three arches of the foot:

Medial longitudinal, lateral longitudinal, and tranverse.

a. Name and locate on a skull the 4 major sutures that connect cranial bones:

Coronal, sagittal, lambdoid suture, and squamous.

a. Name the major sutures of the skull:

Coronal, sagittal, squamous, and lambdoid.

6. What are the two main divisions of the skull?

Cranial and facial bones. (The skull is the body's most complex bony structure.)

10. Name the 5 cavities of the skull:

Cranial, middle and internal ear, nasal, and orbits.

What is the function of the cranium?

Enclose and protect the fragile brain and furnish attachment sites for head and neck muscles.

9. The anterior aspect of the skull is formed by?

Facial bones, and the remainder is formed by a cranium.

59. What are the differences between the female pelvis and the male pelvis?

Female-is modified for childbearing; it tends to be wider, shallower, lighter, and rounder than that of a male.

7. Except for the mandible, what is the shape of most skull bones?

Flat bones.

What are the 5 functions of the facial bones?

Form the framework of the face, contain cavities for the special sense organs of site, taste, and smell, provide openings for air and food passage, secure the teeth, and anchor the facial muscles of expression.

a. What is the function of the vertebral foramen?

Forms the long vertabral canal, through which the spinal cord passes.

What is the function of the Curvatures of the spine?

Increase the resilence and flexibility of the spine, allowing it to function as a spring rather than a rigid rod.

8. What are sutures?

Interlocking joints. Suture lines have a saw-tooth or serrated appearance.

Scoliosis

Is an abnormal lateral curvature that occurs most often in the thoracic region. It is quite common durring late childhood, particularly girls. Other, more severe cases result from abnormal vertabral structure, lower limbs of unequal length, or muscle paralysis. Treated with braces or surgically.

19. Ethmoid bone

Lies between the sphenoid and nasal bones, and forms most of the bony area between the nasal cavity and the orbits.

21. Mandible

Lower jawbone, articulates with the mandibular fossae of the temporal bones via the mandibular condyles to form the temporomandibular joint.

three bones that make up the sternum:

Manubrium, the body, and the xiphoid process.

Kyphosis

Or hunchback, is a dorsally exagerated thoracic curvature. Common in elderly people because of oteoporosis, but may also reflect tuberculosis of the spine, rickets, or osteomalacia.

. Lordosis

Or swayback, is an accentuated lumbar curvature. Can result from tuberculosis or osteomalacia. Tempory lordosis is common in those carrying a large load up front. In an attempt to perserve their center of gravity, these individuals automatically throw back their shoulders, accentuating their lumbar curvature.

32. What are the functions of the vertebral column?

Serves as the axial support of the trunk, transmitts the weight of the trunk to the lower limbs, surrounds and protects the spinal cord and provides attachment points for the ribs and for the muscles of the back and neck.

a. How many true ribs are there?

Seven rib pairs.

c. What is the function of the discs?

Shock absorbers durring walking, running, and jumping.

5. What are the three regions of the axial skeleton?

Skull, vertebral column, and thoracic cage.

60. What is the difference between the false pelvis and a true pelvis?

The false pelvis is really part of the abdomen.

a. What is the function of the intervertebral foramen?

The lateral openings between adjacent vertabrae that the spinal nerves issueing from the spinal cord pass through.

The Pelvic (Hip) Girdle

The pelvic girdle attaches the lower limbs to the axial skeleton. It is formed by a pair of coxal bones, each consisting of three separate bones: the ischium, ilium, and pubis that are fused in adults.

• What do they articulate with?

The ribs.

49. What are Floating ribs?

They have no anterior attachment, instead their castal cartilages lie embedded in the muscles of the lateral wall body.

• Which sections are convex?

Thoracic and sacral.

• Name all of the bones of the wrist:

Trapeziem, trapezoid, scaphoid, hamate, capitate, pisiform, triquetrum, lunate.

48. What is the difference between True and False ribs?

True ribs attach directly to the sternum and false ribs attach indirectly or or entirely lack a sternum attachment.

15. Parietal bones

Two large, rectangular bones on the superior and lateral aspects of the skull, which form the majority of the cranial vault.

45. What is the function of the Bony Thorax?

Vital organ protection, supprts the girdle and upper limbs, and provides attachment points for many muscles of the neck, back, chest, and shoulders.

Foramen magnum

a large opening through which the brain connects to the spinal cord, is located in the base of the occipital bone.

66. Fibula

a sticklike, non-weight-bearing bone. It has expanded ends that articulate proximally

63. Patella

a triangular sesamoid bone that articulates with the femur at the patellar surface.

Paranasal sinuses

air-filled sinuses clustered around the nasal cavity that lighten the skull and enhance resonance of the voice.

major supporting ligaments of the spine

anterior and posterior longitudinal ligaments, which run as continuous bands down the front and back surfaces of the spine.

43. Sacrum

forms the posterior wall of the pelvis. It is formed by five, fused vertebrae in adults, and articulates with the fifth lumbar vertebra superiorly, the coccyx inferiorly, and the hip bones laterally via the sacroiliac joint. The vertebral canal continues through the sacrum, often ending at a large external opening, the sacral hiatus.

Ischium

forms the posteroinferior portion of the coxa

Ilium

forms the superior region of the coxal bone. It articulates with the sacrum, forming the sacroiliac joint, and also with the ischium and pubis anteriorly.

41. Thoracic vertebrae

gradually transition between cervical structure at the top, and lumbar structure toward the bottom. Thoracic vertebrae have a roughly heart-shaped body, which bear two facets on each side for rib articulation: a circular vertebral foramen and superior and inferior articular processes.

20. Sutural, or Wormian, bones

groups of irregularly shaped bones or bone clusters located within sutures that vary in number and are not present on all skulls.

Axis - the 2nd cervical vertebra

has a body, spine, and other typical vertebral processes, as well as a knoblike dens, or odontoid process, projecting superiorly from the body.

Atlas - 1st cervical vertebra

has no body or spinous process. It has articular facets on the superior and inferior surface that articulate with the skull superiorly, and the second cervical vertebra, the axis, inferiorly.

44. Coccyx (tailbone)

is a small bone consisting of four, fused vertebrae that articulate superiorly with the sacrum.

nasal cavity

is constructed of bone and hyaline cartilage, and is formed by the ethmoid, maxillary, and palatine bones, as well as the inferior nasal conchae. • It is divided into right and left parts by the nasal septum, which consists of portions of the ethmoid bone and vomer.

65. Tibia

is the weight-bearing bone of the leg. It is characterized proximally by the medial and lateral condyles that articulate with the femur, and distally by the medial malleolus, an inferior projection on the medial aspect that articulates with the talus.

67. Tarsus

tarsal bones consists of seven tarsal bones that make up the posterior half of the foot.

51. Humerus

the arm is the region extending from shoulder to elbow, and has one bone, the humerus. 52. The humerus is the largest, longest bone of the upper limb. It articulates with the scapula at the shoulder, and with the radius and ulna at the elbow.

62. Femur

the largest, longest, and strongest bone in the body. It articulates proximally with the hip via a ball-like head, and distally with the knee at the lateral and medial condyles.

forearm

the region between the elbow and wrist. It consists of two bones, the ulna and the radius.

40. Cervical vertebrae

the smallest vertebrae. They typically have an oval body, a short, bifid spinous process, a large, triangular vertebral foramen, and a transverse foramen.

The bony thorax consists of?

the thoracic vertebrae dorsally, the ribs laterally, and the sternum and costal cartilages anteriorly.

28. Inferior nasal conchae

thin, curved bones in the nasal cavity that project medially from the lateral walls of the nasal cavity.

Scapulae (shoulder blades)

thin, flat bones that lie on the dorsal surface of the ribcage, articulating with the humerus via the glenoid cavity, and the clavicle via the acromion.

vertebral arch consists of?

two pedicles and two laminae, which collectively give rise to several projections: a median spinous process, two lateral transverse processes, and paired superior and inferior articular processes.