SKELETAL SYSTEM

FUNCTIONS - support and protection
- body movement - muscles "pull" on bones
- blood cell formation =_______________________ - occurs in red bone marrow
- storage of inorganic materials - calcium, magnesium, sodium, potassium...

Organization of the Skeleton

- normally 206 bones with 2 Main Divisions:  ______________ and appendicular

1. Axial: head, neck, trunk, vertebrae, ribs, and ____________________
2. Appendicular: limbs and bones connecting the limbs to the:
      - ________________________ (scapula & clavicle), upper limbs (arms)
      - pelvic girdle (coxal bones), lower limbs (legs)

bone

Long Bone Structure:

1. _______________________ - ends of bone, forms a joint with another bone.
2. _______________________ - shaft of the bone
3. _______________________ - hyaline cartilage covering the ends of bones
4. ______________________ - tough membrane covering over entire bone.

5. ______________________ - within diaphysis, contains bone marrow
                                                         Endosteum- lining of the medullary cavity

      - Red Marrow = produces blood cells | Yellow Marrow =fat storage

Two Types of Bone Tissue

1. _______________________ bone- wall of the diaphysis, solid, strong
2. ________________________ (cancellous) bone - epiphysis.

Microscopic Structure

*Bone tissue is called ______________________ tissue. - The matrix is composed of collagen and inorganic salts

- Osteocytes (mature bone cells)
- enclosed in tiny chambers called lacunae  
- lacuna form concentric rings called lamella

- Canaliculi (canaliculus) connect the osteocytes
- Haversian and Volkmann canals provide passageways for ___________________________

Bone Matrix Coloring (assignment)

Bone Development and Growth:

1. _______________________________bones = broad, flat bones of the skull

2. Endochondral bones = all other bones.

Bones first form as hyaline cartilage. The cartilage then gradually changes into bone tissue - a process called ____________________________,

primary ossification center - diaphysis, increase diameter
secondary ossification center - epiphysis, increase length

epiphyseal disk ( growth plate) between the diaphysis and the epiphysis.

_____________________- produce bone cells called OSTEOCYTES
_____________________ - dissolve bone tissue - a process called RESORPTION.

Basic Types of Joints (articulations):

1. Synarthrotic - immoveable joint, these junctions are called __________________________
2. Amphiarthrotic- slightly moveable joint, vertebrae
3. Diarthrotic - freely moveable joint, have a lubricating fluid called synovial fluid.

                        Ball & Socket       |     Hinge      |      Pivot      |           Saddle

Examples:

Bones of the Skull

1. _______________________ - anterior portion (forehead)
2. _______________________- one on each side of the top part of skull
3. _______________________- side, above ear
4. _______________________ - forms the back of the skull
5. _______________________ - within the cranium, partly visible in eye socket
6. _______________________ - nasal cavity, visible in eye socket
7. ________________________- forms upper jaws
8. ________________________ - lower jaws, only moveable bone of the skull
9. ________________________ - cheek bones

Sutures - connection points between skull bones

1. ___________________________ between frontal and parietal bones
2. ___________________________ between occipital and parietal bones
3. ___________________________ between temporal and parietal bones
4. ___________________________between parietal bones

Fontanels - "soft spots" of an infant's skull, these form sutures as you age, top spot is the anterior fontanel

Foramen Magnum - Large opening through bottom of skull, where the spinal cord enters skull

vertebral column

The Rest of the Bones

Vertebrae - Cervical (C1-C7) = neck | Thoracic (T1-T12) = middle back | Lumbar (L1-L5) = lower back
Sacrum and Coccyx (tailbone)

Ribs - Thoracic Cage, 12 pairs

_______________ - first seven pairs, attach directly to sternum
_______________ - last three pairs
________________ - last two pairs

Pectoral Girdle: Shoulder. Two __________________ (collar bones) and two ___________________ (shoulder blade)

Upper arm - humerus. | Lower arm - _______________________ and ____________________
Wrist - 8 small bones called ____________________________
Hand: Metacarpals | Fingers: _______________________

Pelvic Girdle: Hips. Two large bones called _____________________________

Upper leg - ______________________________ Kneecap: ________________________
Lower leg - _________________ and __________________ (watch your spelling!)
Ankle and Upper foot - 7 bones called _____________________________
Largest is the heel bone called the _________________________________
Foot: _______________________________
| Toes: ___________________________

Carpals and Tarsals

carpalstarsal

Broken Bones

Closed | Open (compound) | Multiple | Comminuted | Greenstick | Spiral