The Skeletal System

• The axial skeleton


  the main trunk of the body is composed of the spine, ribs and breastbone.

  
• The appendicular skeleton


  The extremities of the body, is composed of the shoulders, arm bones, pelvis and leg bones

  
• Cranium


  The cranium is a spherical structure that surrounds and protects the brain. It is made of 8 bones. At birth, the cranium is not solid bone. Spaces called "soft spots allow for the enlargement of the skull as the brain grows.
• Vertebrae


  The spinal column is composed of 26 bones called vertebrae. These bones protect the spinal cord and provide support for the head and trunk. Pads of cartilage tissue, called disks, separate the vertebrae. These disks act as shock absorbers and allow bending and twisting movements. Breakfast at 7 (corvical), lunch at 12 (thoracic), dinner at 5 (lumbar)
• Ribs and sternum


  There are 12 pairs of ribs, 7 of which attach directly to the breastbone. These ribs, along with the sternum (or breastbone) form a "cage" that protects the heart and lungs.
• Shoulder girdle


  The shoulder girdle is made of two clavicles (collarbones) and two scapulas (shoulder bones). They provide attachment for upper arm bones

  
• Arm bones


  Humerus, rasius, ulna, eight carpals, five metacarpals, fourteen phalanges.

  
• Pelvic girdle


  Made of two hip bones that join with the sacrum. The pelvic girdle contains sockets that allow for the attachment of the smooth rounded head of the upper leg bone. There is an opening in these sockets to allow for the passage of nerves and blood vessels to and from the legs.

  
• Leg bones


  Each leg consists of one femur, one patella, one tibia, one fibula, seven tarsals, five metatarsals, fourteen phalanges

  
• Joints


  Joints are areas where two or more bones join together. Connective tissues called bands, called ligaments, help hold long bones together at the joints. Joints allow for different amounts of movement and some allow none at all. For example, fibrous joints in your jawbone hold your teeth in your mouth
• Gliding joints


  Give flexibility to the ankle and your wrist. These joints give you the ability to walk on uneven surfaces and move your hand to the right and the left

  
• Pivot joints


  where bones turn on each other and allow rotation. For example, the top two vertebrae that support the school allow the head to turn to the right and the left.

  
• Ball and socket joints


  Are found in the hip and shoulder. The knoblike end of an arm of thigh bone fits into a bony cup in the shoulder or hip bone. These joints allow the arm or leg to move in almost any direction.

  
• Saddle joints


  Allow a bone to move front to back and left to right. Your thumbs are connected to your hands by saddle joints. This is the joint that gives your thumb the ability to reach across the palm of your hand and touch your other fingers.

  
• Hinge joints


  Allow bones to move in one direction, like a swinging door.

  
• Phalanges


  Fingers AND toes

  
• Cervical vertibrae

  
• Acromian process

  
• Thoracic vertebrae

  
• Lumbar vertebrae