Ch 7: Skeletal System- Gross Anatomy

ESC-2050-52, Human Anatomy, Dr. Farnell

How many bones are there in the body?

206

What are bones segregated into?

axial and appendicular skeleton

How many bones are in the axial skeleton?

80 total bones

How many bones are in the appendicular skeleton?

126 total bones

Bones are classified by what? (5 types)

long, flat, short, and irregular

main part

body

enlarged end

head

constriction between head and body

neck

edge

margin or border

bend

angle

branch off body

ramus

smooth, rounded articular surface

condyle

small flattened articular surface

facet

prominent projection

process

small rounded bump

tubercle

knob

tuberosity

tuberosities on proximal femur

trochanter

near or above condyle

epicondyle

flat, tongue-shaped process

lingula

hook-shaped process

hamulus

horn-shaped process

horn

low ridge

line or linea

prominent ridge

crest or crista

very high ridge

spine

hole

foramen

tunnel

canal or meatus

cleft

fissure

cavity

sinus or labyrinth

general term for a depression

fossa

depression in bone margin

notch

little pit

fovea

deeper, narrow depression

groove or sulcus

What bones does the axial skeleton include and how many of each?

skull → 22

ossicles → 3

Hyoid bone → 1

vertebral column → 26

Thoracic (rib) cage → 25 (12 pairs, 1 sternem)

What are Braincases?

neurocranium, 8 bones, surrounds and protects brains

2 parietals, 2 temporals, occipital, sphenoid, ethmoid

What are the facial bones?

viscerocranium, 14 bones, protect major sensory organs, provide attachment for muscles, 

What is the only freely movable bone in the skull?

the mandible

What are the functions of the skull? What does it contain?

protects brain, supports organs, provides foundation for structures

parietal and frontal bones, sagittal and coronal suture

Suture

where the frontal, parietal, and/or occipital bones are joined

The parietal and occiptial bones of the skull are held together by what suture?

Lambdiod

What does the external occipital protuberance contain? What does it do?

ligamentum nuchae

helps keep head erect

What are the nuchal lines?

neck muscle attachment points

What suture joins the parietal and temporal bones?

Squamous suture

Landmark and Description: Hyoid Bone

• Greater and Lesser horns are what?

• Is the only bone in the body that doesn’t ___, meaning what?

• looks like a what?

attachment points for muscles and ligaments

only bone in the body that doesn’t articulate with another bone (it is floating, only attached by muscles and ligaments)

horseshoe

Landmark and Description: Temporal Bone

• External Auditory Meatus

the external canal of the ear, carries sound to the internal auditory canal

Landmark and Description: Temporal Bone

• Mastoid Process

attachment point for muscles moving the head and for a hyoid muscle

Landmark and Description: Temporal Bone

• Zygomatic process of the Zygomatic arch

form the bony bridge extending from the cheek to the ear

attachment for muscles that move the mandible

Landmark and Description: Temporal Bone

• Styloid process

attachment for the muscles of the tongue, throat, and hyoid bone

Landmark and Description: Temporal Bone

• Mandibular fossa

articulation point between the mandible and skull, forms the TMJ (temporomandibular joint)

Landmark and Description: Temporal Bone

• Carotid canal

internal carotid artery enters the cranial cavity

Landmark and Description: Temporal Bone

• Jugular foramen

internal jugular vein exits the cranial cavity

Landmark and Description: Sphenoid Bone

• Sella Turcica

fossa containing the pituitary gland

(fossa = saddle/ bony house)

Landmark and Description: Sphenoid Bone

• Foramen ovale

opening for a nerve

Landmark and Description: Sphenoid Bone

• Optic foramen

opening where optic nerve passes from eye to cranial cavity

Landmark and Description: Ethmoid Bone

• Cribriform plates

olfactory bulbs and branches of olfactory nerve found here

Landmark and Description: Ethmoid Bone

• Crista galli

attachment/ anchor for meninges (brain connective tissue to the skull)

middle ridge “shark fin” or “roosters crest”

Landmark and Description: Ethmoid Bone

• Perpendicular plate

forms superior portion of the nasal septum

Landmark and Description: Ethmoid Bone

• middle and superior nasal concha

ridge into nasal cavity, increases surface area for the air

Landmark and Features: Occipital bone

• foramen magnum

opening around where the brain and spinal cord connect

Landmark and Features: Occipital bone

• occipital condyles

articulation point between skull and first vertebrate

Landmark and Features: Occipital bone

• hypoglossal canal

opening through which the hypoglossal nerve passes

Landmark and Description: Frontal Bone

• Supraorbital Foramen

“hole above the eye”

opening through which nerves and vessels exit the skull to the skin of the forehead

Landmark and Description: Parietal Bone

• Superior and Inferior Temporal Lines

attachment points for temporalis muscle

Description and Landmark: Zygomatic Bone

• temporal process

“cheek bone”

forms the bony bridge from the cheek to the anterior of the ear

The maxilla is a ___ bone? (R/L)

paired

Description and Landmark: Maxilla

• Alveolar process

ridges that contain the teeth

Description and Landmark: Maxilla

• incisive canal

opening through which a nerve exits the nasal cavity to the roof of the oral cavity

Description and Landmark: Maxilla

• Infraorbital foramen

opening through which a nerve and vessels exits the orbit to the face, supplies the cheeks

Description and Landmark: Maxilla

• palatine process

form the anterior two thirds of the hard palate

The mandible ____ with the temporal bone

articulates

Landmark and Description: Mandible

• body

major, horizontal portion

Landmark and Description: Mandible

• ramus

major, vertical portion

Landmark and Description: Mandible

• Coronoid process

attachment for chewing muscles

Landmark and Description: Mandible

• Mandibular foramen

opeing through which nerves and vessels of the mandibular teeth enter the bone

Landmark and Description: Mandible

• Mental foramen

opening through which a nerve and vessels exit the mandible to the skin of the chin

The palatine bone is a ____ bone (R/L)

paired

Landmark and Description: Palatine

• horizontal plate

• vertical plate

forms the posterior 1/3rd of the hard plate

forms part of the lateral nasal wall

the Lacrimal bone is a ___ bone (R/L)

paired

Landmark and Description: Lacrimal

• nasolacrimal duct and canal

forms a small portion of the orbital wall and the nasolacrimal canal/ duct

what does the nasolacrimal duct do?

drains tears into the nose

The nasal is a ___ bone

Landmark and Description: Nasal

paired

forms the bridge of the nose

Landmark and Description: Vomer

• alae

• vertical plate

attachment points between the vomer and sphenoid

forms part of the nasal septum

Major structures of the anterior skull are?

frontal bone, zygomatic bones, maxillae, and mandible

What bones bear the teeth?

maxilla and mandible

Landmark and Description: Orbits

cone-shaped fossae with their apices oriented posteriorly

sphenoid, ethmoid, palatine, lacrimal, zygomatic, maxilla, frontal are all bones of the what?

Orbit

What divides the nasal cavity into right and left halves?

nasal septum

Nasal conchae (inferior, middle, and superior) all are bones of what? This increases the surface area of the nasal cavity

Nasal Cavity

What are some functions of the vertebral column?

supports weight of head and trunk

protects spinal cord

allows spinal nerves to exit the spinal cord

provides site for muscle attachment

permits movement of head and trunk

How many vertebrate are there in an adult? How many in an embryo?

26

33-24

How many vertebrate fuse to form the sacrum?

How many to form the coccyx?

5

4 or 5

Regions of the back

Cervical → 7

Thoracic → 12

Lumbar → 5

Sacral → 1

Coccyx → 1

The 4 major curvatures in adults allows for what?

proper loading of the spine

At birth the spinal column is what shaped?

When head raised, what appears?

When sitting and walking, what appears?

C shaped

cervical curve

lumbar curve

Lordosis is exaggeration of?

lumbar spine

Kyphosis is exaggeration of the?

thoracic spine

Scoliosis is exaggeration which direction? Commonly along with?

laterally

Kyphosis