BONESSKELETAL 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

1. Support

2. Protection

3. Movement

4. Storage of minerals

5. Production of blood cells

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 BONEA. Periosteum—living membrane

covering bone, except joint

B. Spongy bone—tissue with many spaces, located at end of long bones & in the middle of flat bones

C. Compact bone—very dense, located in shafts of long bones

D. Epiphyseal plate—growth plate

E. Marrow

A. Red—produces RBCs

B. Yellow—mostly fat cells

PARTS OF A BONE

F. Haversian Canals—spaces through which nerves and blood vessels pass

G. Osteoblasts—bone builder cells

H. 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

BALL & SOCKET JOINT

HINGE JOINT

A ball and socket joint allows for radial movement in almost any direction. They are found in the hips and shoulders.

A hinge joint allows extension and retraction of an appendage.

TYPES OF FREE MOVING JOINTS

PIVOT JOINT

GLIDING JOINT

SADDLE JOINT

saddle joint allows movement back and forth and up and down, bot does not allow for rotation like a ball and socket joint.

gliding or plane joint bones slide past each other. Midcarpal and midtarsal joints are gliding joints

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.

NAME THE JOINT TYPEHinge Joint

NAME THE JOINT TYPEFixedJoint

PivotJoint

PivotJoint

NAME THE JOINT TYPEBall & Socket

CARTILAGE1. Some always present

2. Ossification—replacement of cartilage with bone

3. 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