Bones, Bones, and more Bones! Skeletal System Bones, Bones, and more Bones!

Skeletal System https://www.youtube.com/watch?v=QKAg2oIEu9w https://www.youtube.com/watch?v=rDGqkMHPDqE

Objectives I will be able to: describe the functions of the skeletal system. describe the structures of the two subdivisions of the skeletal system. develop and use a model to illustrate the division of axial and appendicular skeletons.

The Skeletal System Components of the skeletal system Bones (skeleton) Joints Cartilages Ligaments

Functions of Bones Support of the body Protection of soft organs Movement due to attached skeletal muscles: “passive” Storage of minerals and fats Blood cell formation

Axial skeleton Appendicular skeleton The Skeletal System Two subdivisions Axial skeleton Appendicular skeleton

The Skeletal System axial skeleton: the skull, vertebral column, ribs, and sternum appendicular skeleton: bones of the limbs and limb girdles that are attached to the axial skeleton

Axial Skeleton The Skull: Formed from cranial and facial bones 8 cranial bones protect the brain. 14 facial bones (12 paired left and right, 2 individual).

Axial Skeleton The Vertebral Column: 24 vertebrae, the sacrum, and the coccyx 7 cervical vertebrae 12 thoracic vertebrae 5 lumbar The vertebrae are separated by fibrocartilage discs that allow the vertebral column to be flexible.

Axial Skeleton The Thorax: The sternum and 12 pairs of ribs All 12 pairs of ribs attach posteriorly to thoracic vertebrae First 7 pairs attach anteriorly to the sternum Last 5 pairs attach indirectly or not at all anteriorly The bony thorax encloses the lungs, heart, and other organs of the thoracic cavity.

 What are the four components of the skeletal system? Name the five functions of the skeletal system? What is the difference between the axial and appendicular skeletons? 1) bones, joints, cartilages, ligaments 2) support of the body, protection of soft organs, movement due to attached skeletal muscles: “passive”, storage of minerals and fats, blood cell formation 3) axial = central skeleton, appendicular = attached skeleton

Appendicular Skeleton The Shoulder Girdles (2): Each composed of a scapula and a clavicle Attach the upper limbs to the axial skeleton Are lightweight, poorly reinforced girdles that allow the upper limbs a great deal of freedom of movement

Appendicular Skeleton Bones of the Upper Limbs: Arm: the humerus Forearm: radius and ulna Hand: carpals, metacarpals, and phalanges

Appendicular Skeleton The Pelvic Girdle: Formed by 2 coxal (hip) bones and the sacrum Each coxal bone is a fusion of the ilium, ischium, and pubis bones The pelvic girdle is securely attached to the vertebral column and the socket for the thigh bone is deep and heavily reinforced to support the weight of the upper body.

Appendicular Skeleton Bones of the Lower Limbs: Thigh: the femur Leg: tibia and fibula Foot: tarsals, metatarsals, and phalanges

 What types of bones form the skull? What are the bones of the upper limbs? What are the bones of the lower limbs? cranial and facial arm, forearm, hand thigh, leg, foot