Chapter 8- Skeletal System

Question 1

Frontal bone

Answer 1

(1 bone): Forms the forehead and the roof of the eye sockets (orbits)

Question 2

Parietal bones

Answer 2

(2 bones): Join together at the top of the head to form the top and sides of the cranial cavity

Question 3

Occipital bone

Answer 3

(1 bone): Forms the rear of the skull

Question 4

Sphenoid bone

Answer 4

(1 bone): Forms a key part of the cranial floor, as well as the floor and side walls of the orbits. With the appearance of a giant moth, the sphenoid bone lies behind and slightly above the nose and throat. It has an indented area called the sella turcica that houses the pituitary gland.

Question 5

Sutures

Answer 5

The bones of the skull join at immovable joints

Question 6

Foramen Magnum

Answer 6

Opening in the skull for the spinal cord to pass through

Question 7

Mandible

Answer 7

(1 bone): Articulates with the temporal bone at the temporomandibular joint (TMJ), making it the only facial bone that can move; it is the largest and strongest bone of the face

Question 8

Which bone or bones form the foundation of the face?

Answer 8

B
Rationale:
Every other facial bone, except for the mandible, articulates with the maxillae.
Zygomatic bones shape the cheeks and form the outer edge of the orbit.
The occipital bone forms the rear of the skull.
The mandible forms the jaw.

Question 9

Temporal bones

Answer 9

(2 bones): Form the sides of the cranium and part of the cranial floor; also contain the structures of the inner and middle ear

Question 10

External auditory meatus

Answer 10

an opening into the ear

Question 11

zygomatic arch

Answer 11

cheekbone

Question 11

Mastoid process

Answer 11

a prominent lump behind the ear

Question 12

styloid process

Answer 12

an attachment point for several neck muscles

Question 13

ethmoid bone

Answer 13

(1 bone): Contributes to the walls of the orbits, the roof and walls of the nasal cavity, and the nasal septum. It lies anterior to the sphenoid bone; the cribriform plate (which forms part of the roof of the nasal cavity) lies on top. Tiny perforations in the cribriform plate allow branches of olfactory nerve to reach the brain.

Question 14

How many bones does the human body have?

Answer 14

206

Question 15

formina

Answer 15

holes in the skull that allow for passage of blood vessels

Question 16

Maxillae

Answer 16

(2 bones): Meet to form the upper jaw; every other facial bone (except for the mandible) articulates with the maxillae; the maxillae form part of the floor of the orbits, part of the roof of the mouth, and part of the floor and walls of the nose

Question 17

Lacrimal bones

Answer 17

(2 bones): Paper-thin bones that form part of the side wall of the orbit

Question 18

Nasal bones

Answer 18

(2 rectangular bones): Form the bridge of the nose (the rest of the nose is shaped by cartilage)

Question 19

Inferior nasal conchae

Answer 19

(2 bones): Contribute to the nasal cavity

Question 20

Vomer

Answer 20

(1 bone): Forms the inferior half of the nasal septum (the superior half is formed by the perpendicular plate of the ethmoid bone)

Question 21

Palatine bones

Answer 21

(two bones): Form the posterior portion of the hard palate, part of the wall of the nasal cavity, and part of the floor of the orbit

Question 22

hyoid bone

Answer 22

the only bone that doesn’t articulate with any other bone
serves as an attachment point for muscles that control the tongue, mandible, and larynx

Question 23

What bone do pathologists look for a fracture in as a sign of strangulation during an autopsy?

Answer 23

Hyoid bone

Question 24

Four pairs of sinuses filled with air open into the internal nose; they lighten the _________ and act as ________ for ________ ________.

Answer 24

skull resonators sound production

Question 25

Named for the bones in which they reside, the ________, ________, and ________ sinuses have well-defined shapes, whereas the ________ sinuses are like sinus cells, having a honey-combed shape.

Answer 25

frontal, maxillary, and ethmoid sphenoid

Question 26

What are the two main differences between the skull of an infant and that of an adult?

Answer 26

1) Suture lines in the skull have not yet fused (Allows bones of skull to shift during passage through birth canal & Allows for rapid brain growth during infancy) 2) Skull contains fontanels (Areas between unfused bones covered by fibrous membranes called fontanels & Over time, fontanels shrink and usually close completely by age 2)

Question 27

Which bone or bones form the foundation of the face? A. Zygomatic bones B. Maxillae C. Occipital bone D. Mandible

Answer 27

Correct answer: B Rationale: Every other facial bone, except for the mandible, articulates with the maxillae. Zygomatic bones shape the cheeks and form the outer edge of the orbit. The occipital bone forms the rear of the skull. The mandible forms the jaw.

Question 28

vertebral column

Answer 28

flexible structure consisting of 33 vertebrae; it holds the head and torso upright, serves as an attachment point for the legs, encases the spinal cord, and allows the body to bend forward, backward, and sideways

Question 29

What are the 5 main sections the vertebral column consists of?

Answer 29

7 cervical vertebrae, 12 thoracic vertebrae, 5 lumbar vertebrae, the sacrum (which consists of 5 fused vertebrae), and the coccyx (which consists of 4 fused vertebrae).

Question 30

What are the four normal curvatures of the spine?

Answer 30

cervical curve, thoracic curve, lumbar curve, and sacral curve

Question 31

Vertebral foramen

Answer 31

An opening that allows for passage of the spinal cord

Question 32

Body

Answer 32

The weight-bearing portion of the vertebra

Question 33

Spinous process

Answer 33

Projects posteriorly from the vertebra (The spinous processes are the bumps you feel when you run your hand along the spine.)

Question 34

Transverse process

Answer 34

Extend from each side of the vertebra; both the transverse and spinous processes serve as attachment points for muscles and ligaments

Question 35

intervertebral disc

Answer 35

Layer of cartilage in between each vertebra Designed to support weight and absorb shock It consists of a gel-like core, called the nucleus pulposus, and a ring of tough fibrocartilage, called the annulus fibrosus

Question 36

herniated disc

Answer 36

Sudden, intense pressure on the intervertebral discs (such as may occur from lifting a heavy object) can cause the annulus of the disc to crack. When this happens, the nucleus pulposus oozes out from the center of the disc and presses on the spinal cord or a spinal nerve, causing pain

Question 37

atlas (C1)

Answer 37

has no body; it consists of a delicate ring and a large vertebral foramen. Depressions on each side of the vertebra articulate with bony projections from the occipital bone of the skull. When the head moves back and forth (such as when nodding “yes”), the projections rock back and forth in these depressions

Question 38

axis (C2)

Answer 38

has a projection called the dens, or odontoid process. The dens projects into the atlas and allows the head to swivel from side to side (such as when saying “no”)

Question 39

What is the purpose of the dens (odontoid process)? A. It allows the head to nod back and forth. B. It allows the head to swivel from side to side. C. It balances the skull on top of the vertebral column. D. It is an attachment point for ligaments.

Answer 39

Correct answer: B Rationale: Depressions on the atlas allow the head to nod. The skull is supported by the atlas. The transverse ligament holds the dens in place, but a ligament does not attach to the dens.

Question 40

Thoracic Cage

Answer 40

consists of the thoracic vertebrae, the ribs, and the sternum; these bones surround and protect the heart and lungs; they also provide an attachment point for the pectoral girdle (shoulder) and upper limbs Expansion and contraction of the thoracic cage cause the pressure changes in the lungs that allow breathing to occur

Question 41

What are the three main regions of the sternum?

Answer 41

manubrium (the broadest portion), body (the longest portion; it joins the manubrium at the sternal angle—also called the angle of Louis—and provides the location of the second rib; xiphoid process (provides an attachment point for some abdominal muscles and is an important landmark for CPR

Question 42

Ribs 1 to 7

Answer 42

(true ribs) attach to the sternum by a strip of hyaline cartilage called costal cartilage

Question 43

Ribs 8, 9, and 10

Answer 43

attach to the cartilage of rib 7; these ribs, as well as ribs 11 and 12, are called false ribs

Question 44

Ribs 11 and 12

Answer 44

(floating ribs) do not attach to any part of the anterior thoracic cage

Question 45

costal margins

Answer 45

lower edges of the thoracic cage the two costal margins meet at the xiphoid process, forming the costal angle

Question 46

pectoral girdle

Answer 46

(or shoulder girdle) supports the arm; it consists of a clavicle (collarbone) and a scapula (shoulder blade). Key landmarks include: The acromion process, which is an extension of the scapula that articulates with the clavicle; The coracoid process, which provides a point of attachment for some of the muscles of the arm; and The glenoid cavity, which is a shallow socket that articulates with the head of the humerus

Question 47

humerus

Answer 47

the long bone of the arm. The enlarged end of the humerus is called the head. Covered with articular cartilage, it articulates with the glenoid cavity of the scapula. A depression on the posterior side of the humerus called the olecranon fossa accommodates the olecranon process of the ulna when the arm is extended. The olecranon process forms the bony point of the elbow. It slides in the olecranon process when the arm is extended

Question 48

radius

Answer 48

one of the two bones of the lower arm; it is located on the same side as the thumb

Question 49

ulna

Answer 49

other bone of the lower arm; it is longer than the radius

Question 50

What do 8 carpal bones form?

Answer 50

the wrist These bones allow the wrist to move back and forth and side to side

Question 51

What do the five metacarpal bones form?

Answer 51

palm of the hand The proximal end of each bone is called the base, the shaft is called the body, and the distal end is called the head. The knuckles that appear when you clench your fist are the heads of the metacarpals.

Question 52

What bones are the fingers formed by?

Answer 52

phalanges The thumb contains two phalanges; the rest of the fingers contain three. The phalanges are identified by the Roman numerals I through V (beginning with the thumb) and as being proximal, middle, or distal.

Question 53

os coxae

Answer 53

two large bones of the hip innominate bones or coxal bone Together, they form the pelvic girdle and are the foundation of the pelvis

Question 54

What three bones fused together does the os coxae bones consist of?

Answer 54

the ilium (a large, flaring section you can feel under the skin), the ischium (the lower, posterior portion), and the pubis (the most anterior portion that joins with the other pubis at the symphysis pubis; a disc of cartilage separates the two pubic bones)

Question 55

pelvis

Answer 55

The combination of both os coxae and the sacrum

Question 56

Iliac crest

Answer 56

the upper, outer edge of the ilium

Question 57

greater sciatic notch

Answer 57

point through which the sciatic nerve passes on its path to the back of the thigh

Question 58

acetabulum

Answer 58

a depression that houses the head of the femur to form the "hip socket"

Question 59

ischial spine

Answer 59

projection into the pelvic cavity

Question 60

ischial tuberosity

Answer 60

supports your body when you are sitting

Question 61

obturator foramen

Answer 61

large hole below the acetabulum that is closed by a ligament

Question 62

What is the os coxae? A. It consists of the clavicle and scapula and supports the arm. B. It consists of three bones fused together to form the foundation of the pelvis. C. It is another name for the sacroiliac joint. D. It is the large, flaring portion of the hip.

Answer 62

Correct answer: B Rationale: The os coxae consist of the ilium, ischium, and pubis fused together. The two os coxae form the pelvic girdle: the foundation of the pelvis. The clavicle and scapula form the pectoral girdle. The os coxae articulates with the sacrum to form the sacroiliac joint. The ilium is the large, flaring section of the os coxae.

Question 63

What is the longest and strongest bone in the body?

Answer 63

Femur

Question 64

tibia

Answer 64

the only lower leg bone that bears weight. It articulates with the femur. The tibial tuberosity (palpable just below the patella) serves as the attachment point for thigh muscles. Medial malleolus is the bony knob on the inner ankle

Question 65

fibula

Answer 65

helps stabilize the ankle; it does not bear any weight. The head of the fibula articulates with the tibia. The distal end of the fibula forms the lateral malleolus of the ankle

Question 66

patella

Answer 66

a triangular sesamoid bone embedded in the tendon of the knee. It consists of cartilage at birth and ossifies between the ages of 3 and 6 years

Question 67

What bones comprise the ankle?

Answer 67

Tarsal bones

Question 68

calcaneus

Answer 68

largest tarsal bone forms the heel and bears much of the body’s weight

Question 69

talus

Answer 69

second largest tarsal bone It articulates with three bones: the calcaneus on its inferior surface, the tibia on its superior surface, and another tarsal bone (called the navicular) on its anterior surface.

Question 70

The second row of tarsal bones consists of three _______ and one large _______ bone

Answer 70

cuneiforms cuboid

Question 71

The __________ form the middle portion of the foot; they are numbered I through V, beginning medially

Answer 71

metatarsals

Question 72

The __________ form the toes. The great toe is called the ________

Answer 72

phalanges hallux

Question 73

To form the hip joint, the head of the femur rests in the: A. ilium. B. ischium. C. obturator foramen. D. acetabulum.

Answer 73

Correct answer: D Rationale: The ilium is the large, flaring portion of the os coxae. The ischium forms the lower posterior portion of the os coxae. The obturator foramen is a hole below the acetabulum.