The Skeletal System Created by Scott Ford 2007

Two Sections of the Skeleton • The Skeletal System can be divided into two main sections: –Axial –Appendicular ** next week

Axial Skeleton

Axial Skeleton • 80 bones make up axial skeleton • The head and trunk • Specifically, the areas that make up the axial skeleton are the: – Skull – Bones (ossicles) of the inner ear – hyoid bone – Chest Retrieved from: http: //upload. wikimedia. org/wikipedia/commons/8/8 b/Axial_skeleton_diagram. svg on 12/7/07

Appendicular Skeleton • 126 bones make up the appendicular skeleton • The bony structure that makes up the shoulder girdle, upper extremities, pelvis and lower extremities Created by Scott Ford © 2007 All rights reserved Retrieved from: http: //en. wikipedia. org/wiki/Appendicular_skeleton on 12/7/07

Parts of the Appendicular Skelton • The Appendicular Skelton is composed of the following groups: – Shoulder girdle – Arm – Hand – Pelvic girdle – Leg – Foot Created by Scott Ford © 2007 All rights reserved Retrieved from: http: //en. wikipedia. org/wiki/Appendicular_skeleton on 12/7/07

A Closer Look: The Skull Created by Scott Ford © 2007 All rights reserved

Skull • Divided into two parts – Cranium – Facial • Cranial Bones form vault to protect the brain • Facial Bones give origins to muscles of facial expression Created by Scott Ford © 2007 All rights reserved

Cranial Bones • There are 5 Cranial Bones, and their job is to protect the brain • The bones are: – Frontal – Temporal (2 x) – Parietal(2 x) – Occipital – Sphenoid Bones Retrieved from: http: //upload. wikimedia. org/wikipedia/commons/d/d 4/Illu_cranial_bo nes. jpg on 12/08/07 Created by Scott Ford © 2007 All rights reserved

Frontal Bone Created by Scott Ford © 2007 All rights reserved

Temporal Bone Created by Scott Ford © 2007 All rights reserved

Parietal Bone Created by Scott Ford © 2007 All rights reserved

Occipital Bone Created by Scott Ford © 2007 All rights reserved

Sphenoid Bone Retrieved from: http: //upload. wikimedia. org/wikipedia/commons/2/2 d/Gray 164. png on 12/8/07 Created

Sutures of the Skull Coronal Suture �Between the Frontal Bone and Parietal Bone Sagittal Suture �Between the two Parietal Bones Lambdoid Suture �Between the Parietal Bones and the Occipital Bones

Facial Bones • These bones serve as attachment points for the muscles of facial expression Retrieved from: http: //en. wikipedia. org/wiki/Image: Illu_facial_bones. jpg on 12/07/07 Created by Scott Ford © 2007 All rights reserved

Facial Bones • • • Mandible: Maxilla (2 x): Nasal Bones (2 x): Palatine

Created by Scott Ford © 2007 All rights reserved

Mandible Created by Scott Ford © 2007 All rights reserved

Maxilla Retrieved from: http: //en. wikipedia. org/wiki/Image: Gray 190. png on 12/7/07 Created by

Nasal Bones Created by Scott Ford © 2007 All rights reserved

Zygomatic Bone Retrieved from: http: //upload. wikimedia. org/wikipedia/commons/2/2 d/Gray 164. png on 12/8/07 Created

Hyoid Bone • A unique part of axial skeleton • Does not articulate with any other bone • Suspended by ligaments and muscles – FYI: Always broken in victims of strangulation Created by Scott Ford © 2007 All rights reserved

Thoracic Cage Created by Scott Ford © 2007 All rights reserved

Thoracic Cage • Made of the sternum, ribs and thoracic vertebrae. Created by Scott

Sternum Consist of 3 parts –Flat bone also known as the breastbone Created by

Ribs • Function of the Ribs: –Protection of thoracic organs –Muscle attachments –Respiration Created

Different types of ribs True � 1 -7 articulated with the sternum directly through their costal cartilage False Ribs � 8 -10 �Articulates to sternum by hitching a rid with costal cartilage of rib 7 Floating Ribs � 11 -12 �Not connected to sternum at all