Bones Skeletal system

What happened to all the bones?? As a newborn you are born with over 300 bones. As an adult you have only 206! What happened to all the other bones? Newborn baby

Can you believe we have 206 bones? Skull and upper jaw—21 bones Ear—3 tiny bones Lower jaw (mandible) Front neck bone (hyoid) Backbone/spine—26 separate bones (vertebrae) Ribs—12 pairs Breast bone Upper limbs—32 bones (2-shoulder, 3 arm, 8 wrist, 19 hand) Lower limbs—31 bones (1 hip, 4 leg, 7 ankle, 19 foot)

Functions of the skeleton Support Protection Movement Storage of minerals Production of blood cells

Protects Vital Organs Axial Skeleton Consists of the following bones: Skull Vertebral column Rib Cage Protects Vital Organs

Appendicular skeleton Arms and leg bones, pelvis, and shoulder areas Movement Production of blood cells Storage of minerals Appendicular Axial

Parts of a bone Periosteum—living membrane covering bone, except joint Spongy bone—tissue with many spaces, located at end of long bones & in the middle of flat bones Compact bone—very dense, located in shafts of long bones Epiphyseal plate—growth plate Marrow Red—produces RBCs Yellow—mostly fat cells

Parts of a bone Haversian Canals— spaces through which nerves and blood vessels pass Osteoblasts—bone builder cells Osteoclasts—bone destroyer cells

Joints Joints are the places where bones meet and touch There are three classification of joints Immovable Slightly Movable Freely Movable

Types of Free moving bone joints

Types of Free Moving Joints Hinge Joint Ball & Socket Joint A hinge joint allows extension and retraction of an appendage. A ball and socket joint allows for radial movement in almost any direction. They are found in the hips and shoulders.

Types of Free Moving Joints Gliding Joint Pivot Joint gliding or plane joint bones slide past each other. Midcarpal and midtarsal joints are gliding joints Saddle Joint Pivot joints allow rotation around an axis. The neck and forearms have pivot joints. Neck--occipital bone spins over the top of the axis. Forearms--radius and ulna twist around each other. saddle joint allows movement back and forth and up and down, bot does not allow for rotation like a ball and socket joint.

Name the Joint Type Hinge Joint

Name the Joint Type FixedJoint Pivot Joint Pivot Joint

Name the Joint Type Ball & Socket

Cartilage Some always present Ossification— replacement of cartilage with bone Bursae—fluid-filled sacs that lubricate some freely moving joints

Tendon vs Ligament Tendon—attaches muscle to bone (sprain) Ligaments—attach bone to bone (strain)

Types of bones Long—have a tubular shaft & articular surface at each end Short or Irregular—are variable in size and shape and are generally compact in nature (hand and foot) Flat—are thin and have broad surfaces (ribs, sternum, hips, scapula)

Diseases and disorders Bursitis—is an inflammation of the bursa, causing pain in the body’s joints Osteoarthritis--(also called degenerative joint disease) occurs when a joint wears out

Diseases and disorders Osteoporosis— disease resulting in the loss of bone tissue. Scoliosis—a side to side curve of the spine

Diseases and disorders Fractures—breaks or cracks in the bone Leukemia—cancer affecting the production of RBCs Leukemia