Musculoskeletal System

Musculoskeletal System

1. Bones

   • protects soft tissue
     • supports the body
       • joints make us move
         • produces blood cells that store calcium and minerals
           • Axial System
             • 80 bones in center of our body
               • they protect our organs, head, neck and torso!
           • Appendicular
             • bones in upper and lower extremedies
               • they anchor the arms legs and head
           • Bone Anatomy
             • compact bone-dense hard bone that makes up the outer wall of bone.
             • Diaphysis-Middle portion of a bone, also called shaft. contains the marrow cavity where blood cells are produced.
             • Epiphysis: End segment of a bone involved in bone growth and made of spongy bone covered with compact bone.
             • Spongy bone: Found in the marrow cavity of diaphysis and epiphysis. Is less dense than compact bone.
             • Periosteum: Fibrous connective tissue covering bones.-contains the blood vessels and nerves that provide nourishment and sensation to the bone.
             • --Bone Marrow: Soft, jello-like tissue in center of some bones. --Red bone marrow produces red blood cells, platelets, and all but one kind of white blood cell. --Yellow bone marrow stores fat but may turn into red marrow when the body is ill.

2. Joints

   • Synarthroses joints: do not move at all, connected by a thin layer of connective tissue, example: joints in your skull
   • Amphiarthroses joints: move a little, connected by cartilage with strong fiberous connective tissue, example: joints in your backbone
   • Diarthroses joints: Freely moveable and connected with ligaments, example: your knee --contain ligaments: are bands of fibrous tissue that are not as strong as cartilage, but are more flexible. --also contain synovial fluid: Viscous colorless fluid that bathes movable joints and between the bones of vertebrates. It nourishes and lubricates the cartilage at the end of each bone
     • Six types of Diarthroses joints::
       • 3. Saddle joints can be found in the fingers and thumbs.
       • 2. Ellipsoid joints can be found in the knee. When the knee is extended, it does not allow rotation. When it is flexed, it allows for limited rotation
       • 1. Ball and Socket joints can be found in the hip. These joints allow for movement in many directions.
       • 4. Hinge joints can be found in the elbow between the humorous and the ulna. A hinge joint works just like a door hinge, allowing motion in only one direction.
       • 5. Pivot joints can also be found in the elbow between the ulna and the radius. This type of joint allows one bone to rotate about the other.
       • 6. Gliding joints can be found between the carpals in the wrists. These joints allow limited movement between the bones as one glides past the other.

3. 3 types of Muscle:

   • Smooth muscle --contained in the walls of your hollow organs, such as the stomach and bladder. --not attached to bones; is involuntary.
   • Skeletal muscle --Attach to the skeleton, holding it together and enabling movement. --Striated and voluntary. --Attached to the bone by tendons.
   • Cardiac muscle --Contained in your heart. --Tissue has interlocking fibers that allow contractions to move quickly through the organ. --Involuntary.

4. Without your musculoskeletal system, you wouldn’t have anything to support your body, help you move, or protect your organs.