Skeletal System
The skeletal system is divided into two main categories: the axial and appendicular skeletons. The axial skeleton includes the skull (22 bones), ribs (12 pairs), sternum, and vertebral column, while the appendicular skeleton consists of the shoulder girdle, arms, pelvic girdle, and legs. Each section serves crucial roles, such as protecting vital organs, supporting weight, and facilitating movement. Key features include the cranial bones, vertebrae, and various bones in the limbs and hands, which together provide structure and support for the body.
Skeletal System
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Presentation Transcript
Skeleton System • The skeletal system is broken into 2 categories • Axial • Skull • Ribs • Sternum • Vertebral column • Appendicular • Upper extremity • Lower extremity
Skull • Made up 0f 22 bones • 8 bones fused together make the cranium • Frontal • Parietal • Temporal • Occipital • 14 bones make up the face • Mandible • Maxilla • Zygomatic • Nasal bones • Only joint that moves in the skull is the temporomandibular joint • mandible forms a hinge with temporal bone
Ribs • Purpose of the ribs are to protect the heart and lungs • There are 12 pairs of ribs • 1-7: True ribs • 8-12: False ribs • 11-12: Floating ribs • Sternum • Also called the “breastbone” • Sometimes used as a painful stimulus • 3 parts • Manubrium • Articulates with clavicle • Body • Articulates with ribs 2-7 • Xiphoid process • Attachment for rectus abdominis • Also a landmark for CPR
Vertebral Column • Spinal Column or vertebral column stretches from the base of skull to coccyx • Composed of bones called vertebrae • Intervertebral disks separate body of each vertebrae • Vertebrae has ligaments in front and back to help keep column together • Each vertebrae has 3 parts • Body • Spinous Process • Vertebral foramen • Holds spinal cord
Sections of the Vertebral Column • There are 5 sections to the vertebral column • 7 Cervical vertebrae • Smallest vertebra • 12 Thoracic vertebrae • Articulate with the ribs • 5 Lumbar vertebrae • Supports most of the body’s weight • Sacrum • Composed of 5 fused vertebrae • Coccyx • Composed 4 fused bones • Also called the “tail bone”
Shoulder Girdle • Consists of 2 bones • Scapula • Also called the shoulder blade • Free floating bone between ribs 2 & 7 posteriorly • Clavicle • Also called the collar bone • Attaches to axial skeleton
Arm • Humerus • Long bone located in the upper arm • Forearm (2 bones) • Radius • Lateral long bone in the forearm • Ulna • Medial long bone in the forearm
Hand • There are 27 bones that make up the hand • Carpals • 8 small bones that make up the wrist • Metacarpals • 5 long bones that make up the palm • Named according to their position in the hand • Ex. 1st metacarpal is thumb, 5th is little finger • Phalanges • 14 bones that make up the fingers • Also called digits • Each finger has 3 bones • Each thumb has 2
Pelvic Girdle • Consists of 3 bones • Attaches lower limb to axial skeleton • Transmits weight of upper body to lower limb • Supports pelvic bones • 3 main bones • Ilium • Largest part of pelvic girdle • Ischium • Located posteriorly • Called “sit bones” • Pubis • Located anteriorly • Come together to form pelvis
Leg • Consists of 4 bones • Femur • Longest and strongest bone in the body • Built for stability, not flexibility • Patella • Also called knee cap • Tibia • Long bone on the medial aspect of leg • 90% weight bearing • Fibula • Long bone on the lateral aspect of leg • 10% weight bearing
Foot • Consists of 26 bones • Tarsals • 7 bones that make up the ankle • Metatarsals • 5 long bones of the foot • Name according to their position in the foot • Phalanges • 14 bones that make up phalanges • Each toe contains 3 • Each toe contains 2
