skeletal system 2 n.
Skip this Video
Loading SlideShow in 5 Seconds..
Skeletal System-2 PowerPoint Presentation
Download Presentation
Skeletal System-2

Loading in 2 Seconds...

play fullscreen
1 / 59

Skeletal System-2 - PowerPoint PPT Presentation

  • Uploaded on

Skeletal System-2. Honors Anatomy for copy. Essential Question. What is the main contribution the axial skeleton makes to homeostasis?. Divisions of the Skeleton. AXIAL SKELETON Skull Cranium Face Hyoid Auditory Ossicles Vertebral Column Thorax . APPENDICULAR SKELETON:

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about 'Skeletal System-2' - elise

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
skeletal system 2

Skeletal System-2

Honors Anatomy

for copy

essential question
Essential Question

What is the main contribution the axial skeleton makes to homeostasis?

divisions of the skeleton
Divisions of the Skeleton
  • Skull
    • Cranium
    • Face
  • Hyoid
  • Auditory Ossicles
  • Vertebral Column
  • Thorax


Pectoral Girdle

Upper Limbs

Pelvic Girdle

Lower Limbs

types of bone
Types of Bone
  • bones fall into 1 of 5 main types based on shape:
    • Long
    • Short
    • Flat
    • Irregular
    • Sesamoid
short bones
Short Bones
  • somewhat cube-shaped
  • nearly equal in length as width
  • consist of:
    • spongy bone except @ surface
flat bones
Flat Bones
  • Composed of:
    • 2 nearly parallel plates of compact bone enclosing spongy bone inside
  • Function:
    • give considerable protection
    • place for muscle attachment
irregular bones
Irregular Bones

complex shapes (do not fit in other categories)

vary in amt spongy bone

sesamoid bones
Sesamoid Bones

develop w/in certain tendons where there is considerable friction, tension, & physical stress

function: protect tendon from excessive wear & tear

vary in # person to person but everyone has 2 patella which develop in quadriceps femoris tendon

sutural bones
Sutural Bones

classified by location (w/in a suture: a seam between 2 cranial bones)

not everyone has them

bone surface markings
Bone Surface Markings
  • 2 major types:
  • depressions & openings
    • form joints or allow passage of vessels & nerves
  • processes
    • projections or outgrowths that either help form joints or serve as attachment points for ligaments & tendons
  • 22 bones in 2 categories:
  • Cranium
    • 8 bones that form cranial cavity
      • 1 frontal bone
      • 2 parietal bones
      • 2 temporal bones
      • 1 occipital bone
      • 1 sphenoid bone
      • 1 ethmoid bone

2. Facial Bones

14 bones that form the face

  • 2 nasal bones
          • 2 maxillae
          • 1 mandible
          • 2 zygomatic
          • 2 lacrimal
          • 2 palantine
          • 2 inferior nasal conchae
          • 1 vomer
skull cavities
Skull: Cavities

Cranial Cavity

Nasal Cavity


Paranasal Sinuses

Middle & Inner Ear Cavities

functions of cranial bones
Functions of Cranial Bones

protecting brain

stabilizing position of brain, vessels, & nerves through attachments to the meninges

outer surfaces provide large areas of attachment for muscles that move parts of the head & some for facial expression

parietal bones
Parietal Bones

form greater portion of sides & roof of cranial cavity

temporal bones
Temporal Bones

form inferior, lateral aspects of the cranium & part of the cranial floor

its zygomatic process forms the lateral half of the zygomatic arch

mandibularfossa: where condylar process of mandible forms TMJ (temporal mandibular joint)

temporal bones1
Temporal Bones

external auditory meatus: ear canal

mastoid: posterior & inferior to external auditory meatus, contains “air cells” (mastoiditis: inflammation in air cells)

temporal bone petrous portion
Temporal Bone: Petrous Portion

base of skull between sphenoid & occipital bones

houses middle & inner ear

Carotid foramen & Jugular foramen

temporal bones2
Temporal Bones

internal auditory meatus: passage of Cranial nerves VII (facial n.) and VIII (vestibulocochlear n.)

styloid process: point of attachment for muscles & ligaments of the tongue & neck

occipital bone
Occipital Bone

forms back of head & most of base of skull

foramen magnum: large hole spinal cord passes thru,

occipital condyles: articulate with 1st cervical vertebra (atlas)

sphenoid bone
Sphenoid Bone

middle base of skull

*articulates with all other cranial bones

shape resembles a bat

sphenoid bone1
Sphenoid Bone

sellaturcica: (Turkish saddle) the “seat” of the saddle is the hypophysealfossa: where the pituitary gland sits

optic foramen: between body & lesser wings, cranial nerve II (optic n.) and opthlamic artery pass thru

ethmoid bone
Ethmoid Bone

“like a sieve”

midline of anterior part of cranial floor, anterior to sphenoid, posterior to nasal bones

cribiforme plate: forms roof of nasal cavity, the holes of the sieve where olfactory nerves pass from roof of nasal cavity to brain

cristagalla: triangular process which serves as pt of attachment for meninges of brain

facial bones
Facial Bones
  • shape of face changes dramatically during 1st 2 yrs of life:
    • brain & cranial bones expand
    • 1st set of teeth erupt
    • paranasal sinuses enlarge
    • growth of face stops ~16 years old
facial bones1
Facial Bones

14 facial bones:

2 nasal bones

2 maxillae

2 zygomatic bones

1 mandible

2 lacrimal bones

2 palatine bones

2 inferior nasal conchae

1 vomer

nasal bones
Nasal Bones

form part of the bridge of the nose (rest is cartilage)


= upper jaws

*articulate with every bone in face except the mandible

form part of floor of orbits, parts of nasal cavity, & most of the hard palate (bony roof of mouth)

each one has large maxillary sinus

alveolar process is small arch that contains the alveolar sockets for upper set of teeth

cleft palate cleft lip
Cleft Palate & Cleft Lip
  • 10-12 wks gestation the palatine processes of maxillae typically join
  • not doing so  cleft palate +/- cleft lip
    • speech & swallowing can be affected
    • many ear infections
    • reparative surgery recommended 1st few wks of life / surgery needs to be completed by 12 – 18 mos b/4 speech: speech therapy & orthodontic care frequently necessary
zygomatic bones
Zygomatic Bones

“cheekbones”: the temporal process of the zygomatic bone articulates with the zygomatic process of the temporal bone

also part of floor of orbit

inferior nasal conchae
Inferior Nasal Conchae

inferior to the middle nasal conchae of the ethmoid bone forming part of lateral wall of nasal cavity

same function as superior & middle conchae: swirling inhaled air to deposit particulates but not involved in sense of smell


Δ shaped bone on the floor of nasal cavity forming inferior portion of nasal septum


largest & strongest facial bone (lower jaw)

alveolar processes hold lower teeth sockets

mental foramen: dentist numb mental nerve


an immovable joint in an adult found only between skull bones & holds most skull bones together

name generally reflects bones they unite

hyoid bone
Hyoid Bone

“U-shaped “

*does not articulate with any other bone in skeleton

suspended by ligaments from styloid process of temporal bone

in anterior neck between mandible & larynx

function: supports tongue

*frequently fractured during strangulation

vertebral column
Vertebral Column

Fetus has anteriorly concave curve

3 mos old when holds head cervical curve develops

lumbar curve develops as infant sits up, stands, walks

intervertebral discs
Intervertebral Discs
  • between bodies of consecutive vertebra
    • under compression they flatten & broaden
    • harden, less elastic w/aging & narrow  loss of height
  • annulus fibrosus: outer fibrous ring
  • nucleus pulposus: inner soft, highly elastic
parts of a vertebra
Parts of a Vertebra
  • Body
    • thicker, anterior portion, weight bearing portion
  • Vertebral Foramina
    • contains spinal cord, adipose, areolar CT, blood vessels
  • Spinous Process
    • 1 of 7 processes, posterior, palpable on back of body

Transverse Processes: on each side, extending laterally

vertebrae 1 st 2 nd cervical
Vertebrae: 1st & 2nd Cervical
  • Atlas
    • ring-shaped
    • articulates with condyles of occipital bone
    • allows you to nod head “yes”
  • Axis
    • 2nd cervical v.
    • allows you to shake head “no”
typical thoracic vertebrae
Typical Thoracic Vertebrae

T-1 to T-12

larger & stronger than cervical v.

distinguishing feature: articulate with ribs (facets on transverse processes of T-1 to T-10

typical lumbar vertebrae
Typical Lumbar Vertebrae

L-1 to L-5

largest & strongest of the vertebrae

processes are short & thick


triangular bone formed by union of S-1 to S-5

fusion begins ~16, complete by age 30

female: shorter, wider, more curved S-2 to S-3


small triangle

formed by fusion of 4 coccygeal v. (Co-1 to Co-4), start between 20 & 30

females points inferiorly; males it points anteriorly

  • refers to entire chest
  • skeletal part of thorax is thoracic cage
    • Sternum
    • Ribs

aka “breastbone”

flat bone in center of anterior thorax

3 bones that fuse by age 25



superior portion

suprasternal notch

clavicular notches

articulates with costal cartilage of 1st & 2nd rib

sternal angle: where it articulates with body


2. Body

middle & largest portion

articulates with costal cartilage of 2nd thru 10 ribs


3. Xiphoid Process

cartilagenous in infancy

not completely ossified until ~age 40

avoid it during CPR

ribs 12 pair
Ribs: 12 Pair

increase in length 1st thru 7th then decrease in length to 12th

1st thru 7th ribs (true ribs) have direct anterior attachment to sternum by strip of hyaline cartilage which contribute to elasticity of thoracic cage

8th thru 10th ribs attach to each other & then to cartilages of 7th rib

11th & 12th ribs: floating ribs


all 12 attach posteriorly to vertebrae

Parts of a Rib





Costal Angle

abnormal curvatures of spine
Abnormal Curvatures of Spine


lateral bending

usually in thoracic region

abnormal curvature of spine
Abnormal Curvature of Spine


exaggeration of the thoracic curve

seen in TB of spine, congenital malformation, elderly