 There are 206 bones in an adult human.  The human skeleton is divided into two parts  Axial; includes skull ribs and vertebral column  Appendicular; includes arms legs shoulders pelvis Skeletal System

 supports the body.  protects internal organs.  provides for movement.  stores mineral reserves.  provides a site for blood cell formation  provides a site for blood cell formation. Functions:

Bones are a solid network of living cells and protein fibers that are surrounded by deposits of calcium salts. Skeletal System

Osteocytes Osteocytes, mature bone cells, which are embedded in the bone matrix.  Other bone cells  Osteoclasts, break down bone.  Osteoblasts, produce bone. Skeletal System

 Bone marrow is a soft tissue inside the cavities within bones. There are two types  Yellow marrow is made up of fat cells.  Red marrow produces red blood cells, platelets, and some white blood cells. Skeletal System

The function of the muscular system is movement. Function of the Muscular System

There are three different types of muscle tissue: Skeletal Smooth Cardiac

Skeletal muscles generally remain in a state of partial contraction called resting muscle tone. Muscle tone is responsible for keeping the back and legs straight and the head upright, even when you are relaxed.  are usually attached to bones.  are responsible for voluntary movements.  are sometimes called striated muscles. Skeletal Muscles:

Smooth muscles:  are usually not under voluntary control.  are spindle-shaped.  are not striated.  are found in many internal organs and blood vessels.

Cardiac muscle:  is only found in the heart.  is striated.

Opposing Muscles Contract and Relax Copyright Pearson Prentice Hall

Opposing Muscles Contract and Relax Copyright Pearson Prentice Hall

What do your muscles do to help maintain your body temperature? Shivering Goose bumps