The Skeletal System - Axial

Question 1

Number of bones in human body, axial, and appendicular skeleton

Answer 1

206
80
126

Question 2

Axial skeleton

Answer 2

Bones that lie around the longitudinal axis of the body

Question 3

What bones are in the axial skeleton?

Answer 3

• skull bones
• auditory ossicles (ear bones)
• hyoid bone
• ribs
• sternum (breastbone)
• bones of vertebral

Question 4

5 types of bones

Answer 4

1. long
2. short
3. flat
4. irregular
5. sesamoid

Question 5

Long bone + examples

Answer 5

• greater length than width
• slightly curved for strength
  ex: femur, tibia, fibula, humerus, ulna, radius, phalanges

Question 6

Short bone + examples

Answer 6

• cube shaped; equal length and width
• spongy bone with compact on outer surface
  ex: carpal and tarsal

Question 7

Flat bone + examples

Answer 7

• thin composed of 2 parallel plates of compact bone with a layer of spongy in between
• protection and muscle attachment site
  ex: cranial bones, sternum, ribs, scapulae

Question 8

Irregular bones + example

Answer 8

• complex in shape
• vary in amount of spongy and compact bone
  ex: vertebrae, hip, facial bones, and calcaneus

Question 9

Seasamoid

Answer 9

Develop in certain tendons where there is considerable frictions, tension, and physical stress

Question 10

Bone surface markings

Answer 10

• structural features adapted for specific functions

- not present at birth; develop from tension

Question 11

Types of surface markings

Answer 11

Depressions and openings- allows passage of soft tissues or form joints

Processes- projections or outgrowths that either help form a joint or as a attachment sit

Question 12

Types of depressions

Answer 12

• fissure
• foramen
• fossa
• sulcus
• meatus

Question 13

Fissure

Answer 13

-narrow slit between adjacent parts of the bone

Question 14

Foramen

Answer 14

-opening through which BV, nerves, or ligaments pass

Question 15

Fossa

Answer 15

-shallow depression

Question 16

Sulcus

Answer 16

-furrow along bone surface that accommodates BV, nerve, or tendon

Question 17

Meatus

Answer 17

-tube like opening

Question 18

Processes that form joints

Answer 18

Condyle- large, round protuberance with smooth articular surface at the end of the bone

Facet- smooth, flat, slightly concave or convect articular surface

Head- usually rounded articular projection supported on neck of bone

Question 19

Processes that form attachments

Answer 19

Epicodyle- typically roughened projection above condyle

Line- long, narrow ridge or border

Spinous- sharp, slender projection

Trochanter- very large projection

Tubercle- variably sized rounded projection

Tuberosity- variable sized project that has a rough, bumpy surface

Question 20

Skull

Answer 20

• 22 bones
• two categories:
  1. cranial
  2. facial

Question 21

Cranial bones

Answer 21

• 8 bones form the cavity

- frontal, 2 parietal, 2 temporal, occipital, sphenoid, and ethmoid

Question 22

Facial bones

Answer 22

• 14 bones form the face

- 2 nasal bones, 2 maxillae, 2 zygomatic, mandible, 2 lacrimal, 2 palatine, 2 inferior nasal conchae, and volmer

Question 23

Skull function

Answer 23

protect and support special sense organs and the brain
-forms: nasal cavity, orbits, paranasal sinuses, and small cavities which house organs involved in hearing and equilibrium

Question 24

Frontal bone

Answer 24

Forms the forehead, roof of the orbits, and anterior part of cranial floor

Question 25

Parietal bones

Answer 25

- sides and roof of cranial cavity - internal surfaces contain depressions that accommodate BV - sagittal, squamous, lambdoid, and coronal suture

Question 26

Temporal bones

Answer 26

Inferior lateral aspects of the cranium and part of the cranial floor

Question 27

Occipital bone

Answer 27

Back of head

Question 28

Sphenoid bone

Answer 28

- middle part of the base of the skull - keystone bone: hold everything together - butterfly shaped

Question 29

Ethmoid bone

Answer 29

- delicate - anterior part of cranial floor medial to orbits - looks like sponge - anterior to sphenoid and posterior to nasal - supporting structure of nasal cavity

Question 30

Mandible

Answer 30

- lower jawbone - largest and strongest - only moveable bone

Question 31

Maxilae

Answer 31

- upper jawbone | - articulates with every bone in face except mandible

Question 32

Vomer + function

Answer 32

- roughly triangular bone on the floor of nasal cavity | - forms inferior portion of bony nasal septum

Question 33

Nasal bone + function

Answer 33

- small, flattened, rectangular-shaped bones that bridge the nose - protect upper entry to nasal cavity and attachment site

Question 34

Zygomatic bone + function

Answer 34

- cheekbones | - prominences of cheeks and part of lateral wall and floor of each orbit

Question 35

Palatine bone + function

Answer 35

- L shaped - form posterior portion of hard palate - part of the floor and lateral wall of nasal cavity - small portion of the floors of the orbits

Question 36

Inferior nasal conchae + function

Answer 36

- scroll like bones - form part of inferior lateral wall of nasal cavity - increase surface area, help filter air - only superior nasal conchae are involved in smell

Question 37

Lacrimal bone

Answer 37

- fingernail size and shape | - smallest bone of face

Question 38

Nasal septum components

Answer 38

Vomer, septal cartilage, and perpendicular plate of ethmoid bone

Question 39

Orbit components

Answer 39

- cranial bones (frontal, sphenoid, ethmoid) | - facial (palatine, zygomatic, lacrimal, maxilla)

Question 40

Orbit parts

Answer 40

Roof= frontal and sphenoid Lateral wall= zygomatic and sphenoid Floor= maxilla, zygomatic, and palatine Medial wall= maxilla, lacrimal, ethmoid, and sphenoid

Question 41

Orbit openings

Answer 41

- optic foramen - superior orbital fissure - inferior orbital fissure - supraorbital foramen - lacrimal foreman

Question 42

Sutures + examples

Answer 42

- immovable joint the holds bones together | ex: coronal, sagittal, lambdoid, squamous

Question 43

Paranasal sinuses + function

Answer 43

- cavities in facial bones near the nasal cavity - allows skull to increase in size w/o change in weight - increase the SA of nasal mucosa - echoing chamber

Question 44

Fontanels

Answer 44

Soft spot in babies