Chapter 7: Bones + Axial Skeleton

What are the structures of bones?

1. Articulations

2. Landmarks (bone marking)

3. Foramina

What is Articulations?

Where bones come together/meet

What is landmarks (bone markings)

Areas where muscle/ligaments attach- Recognizable features

What is foramina?

Openings in a bone, cause/allow nerves and blood vessels to pass through

What is the Axial Skeleton?

Central framework of the body

How many bones does the human body have?

206 bones

What two ways does the skeletal system split into?

1. Axial

2. Appendicular

How many bones are in the Axial Skeleton?

80

How many bones are in the Appendicular Skeleton?

126

What are the functions of the Axial Skeleton?

• Protect important organs (brains, spinal cord, heart, lungs)

• Support & hold the body

• Attach, give muscles & ligaments place to attach

What are the 3 main parts of the Axial Skeleton?

1. Skull→ protect brain

2. Vertebral Column→ protect spinal cord

3. Thoracic Cage→ protect heart & lungs

What is the function of the skull in the Axial Skeleton?

Protect the brain and help protect openings for respiratory & digestive system.

How many bones does the skull contain?

29

How is the skull split up in the Axial Skeleton?

Cranial, Facial, Auditory and Hyoid

How many bones does the cranial have?

8= brain protection

How many bones does the facial have?

14= make up face

How many bones does the auditory have?

6

How many bones does the hyoid have?

1

Bones for the Cranial:

• Partietal (2)

• Temporal (2)

• Frontal (1)

• Occipital (1)

• Ethmoid(1)

• Sphenoid (1)

Bones of the Auditory:

• Malleus (2)

• Incus (2)

• Stapes (2)

Bones of the Facial:

• Maxilla (2)

• Zygomatic (2)

• Mandible (1)

• Nasal (2)

• Palatine (2)

• Inferior Nasal Concha (2)

• Lacrimal (2)

• Vomer (1)

What are the deep facial bones?

Palatine, Inferior Nasal Concha and Vomer

What is the function of the Thoracic Cage in the Axial Skeleton?

Protect vital organs in the chest

The thoracic cage contains how many bones?

25

What does the Thoracic Cage contain?

Sternum and Ribs

How many portions does the Thoracic Cage contain?

3

What are the 3 portions of the Thoracic Cage?

Manubrium, Body and Xiphoid

What is the Manubrium?

Top portion, wide connects collarbone to first pair of ribs.

What is the Body?

Middle, long and flat

-3rd, 4th, 5th, 6th, 7th attach

What is the Xiphoid?

Low, bottom, pointed end/bottom

How many ribs are ther?

24 (12 pairs)

What are the 3 type of ribs?

True

False

Floating

What/Which are True Ribs?

Connect directly to the sternum with their own cartilage

Ribs: 1-7

What/Which are False Ribs?

Connect to the sternum indirectly by attaching to the cartilage of the rib above them.

Ribs: 8-10

What/Which are Floating Ribs?

Do no connect to the sternum at ALL

Ribs: 11-12

Order of the Thoracic Cage:

Sternum→ True Ribs→ False Ribs→ Floating Ribs

Main function of the Vertebral Column?

Provide support for the body, hold weight of upper body, protect spinal cord and allow flexible movement/posture.

How many bones are in the Vertebral Column?

26

What makes up the Vertebral Column?

• Vertebrae

• Sacrum

• Coccyx

How many regions are in the Vertebrae?

3 regions: (24)

Cervical (7)

Thoracic (12)

Lumbar (5)

What is the Sacrum?

1 bone, which is five fused bones that form the wall of the pelvis

What is the coccyx?

1 bone, which is 4 fused bones known as the tailbone

What is the Skull Sutures?

Immovable joints between the skull bones

How many skulls sutures are there total?

7 named sutures

What are the major cranial sutures?

4 to 5

=Coronal, Sagittal, Lambdoid, Squamous, Metopic

What is the Coronal Suture?

Side to side, joins frontal to parietal

What is the Sagittal Suture?

Front to back, down to middle, join the two parietal bone

What is the Lambdoid Suture?

Run across the back, join the parietal and temporal bones to the occipital bone.

What is the Squamous Suture?

Located in sides, join the parietal and temporal bones

What is the Metopic Suture?

Run down the middle of forehead, usually fused in infants and adults

What are sinuses?

Hollow cavities inside the skull

What is the function of sinuses?

They create air filled cavities and decrease weight of the skull so there is less solid bones.

What lines the sinuses?

Mucous Membrane

What are the functions of the ethmoid bone?

• Skull Floor

• Nasal Cavity

• Nasal Septum'

• Eye Socket

• Sinuses

What do the Inferior Nasal Conchae?

• Create air turbulence

• Increase surface area

• Warm/humidify inhaled air

What is the zygomatic bone?

Cheekbone

What are the marks on the zygomatic bone?

Temporal process

What is the Lacrimal Bone?

Small bone near the eye

What are the marks on the Lacrimal Bone?

Lacrimal Sulcus

What is the vertebral body?

Main part of the vertebra that transfers weight along the spine

What is the vertebral arch?

Back part of the vertebra that forms posterior (back) margin of the vertebral foramen

What is the vertebral foramen?

Opening in the vertebra where spinal cord passes

What are articular processes?

Projections that help connect one vertebra to another

What are the articular processes located between?

Laminae & Pedicles