1. Skeletal System
Chapter 7

2. Functions
1. Support – strong, rigid nature allows for structural support
2. Protection – Shields organs, ribcage surrounds heart and lungs
3. Aid in Movement – serves as place of attachment for skeletal muscles
4. Blood Cell Formation – hematopoiesis: manufacturing process for blood cells, occurs in red marrow
5. Storage – calcium and phosphate, which are needed for muscle contraction, nerve cell functioning, and movement of materials across cell membranes

3. Bone Structure

4. Types of Bones Long bone – Greater in length than in width
designed to absorb stress from body weight
found in arms, forearms, hands, thighs, legs, and feet

5. Types of Bones Short Bone – equal in length and width (cube shaped)
Found in ankles and wrists

6. Types of Bones Flat Bone – thin and flat
Found in cranium of head, ribs, scapulae, and sternum

7. Types of Bones
Irregular – complex shapes
Vertebrae, facial bones

8. Types of Bones
Round (sesamoid) Bones – small, nodular, usually embedded in tendons
Kneecap

9. Parts of a Long Bone
Diaphysis – long, central shaft of bone (between ends)
Epiphyses – extreme ends of a bone, each end forms a joint (articulation) with another bone
Articular Cartilage – thin layer of hyaline cartilage along outer surface of epiphyses near joint

10. Parts of a Long Bone
Periosteum – sheet of dense connective tissue that covers bone (except where there is articular cartilage)
attaches to outer surface of bones by protein fibers
large supply of blood vessels (bone nourishment)
contains bone cell called osteoblast (bone growth and repair)

11. Parts of a Long Bone
Compact bone – dense matrix, forms thick walls in diaphysis, thin layer in epiphyses
Spongy bone – spaces filled w/ red marrow, occupies epiphyses

12. Parts of a Long Bone
Medullary cavity – surrounded by sponge bone layer; space w/in shaft of long bones that contains yellow marrow (fat storage)
Endosteum – thin membrane that lines the interior surface of the medullary cavity