Ch. 7 Axial Skeleton: Thoracic Cage

Question 1

Thoracic Cage

Answer 1

Includes thoracic vertebrae, ribs, sternum, and costal cartilages

Protects heart, lungs, other organs

Supports pectoral girdle and provides attachment points

Intercostal spaces hold muscles that aid in breathing

Question 2

Sternum

Answer 2

3 bones:

• -Manubrium (jugular notch [superior], sternal angle [inferior])
• -Body
• -Xiphoid process

Articulates w/:

• -clavicles
• -ribs and costal cartilages

Question 3

Rib Cage

Answer 3

Fxn: protect internal organs, aid in respiration

12 pairs of ribs

All ribs attach posteriorly to thoracic vertebrae

1st 7 attach to sternum by costal cartilages (true ribs)
8-12 are false ribs - do not have direct attachment to sternum
11-12 are “floating ribs” - don’t attach anteriorly at all

Question 4

Rib Structure

Answer 4

Shaft (body): main part of rib
Rib articulates w/ vertebra at head and tubercle
“Neck” is thinner region between head and tubercle
Head has 2 “demifacets” - one demifacet articulates w/ body of “its” vertebra; one articulates w/ facet on traverse process of vertebra
Head articulates w/ vertebral body
Tubercle articulates w/ transverse process