SKELETAL SYSTEM. Functions of the Skeletal System. Bones are made of OSSEOUS TISSUE Support and Protection Body movement Blood cell formation (bone marrow) - hemopo ie sis Storage of inorganic materials (salt, calcium, potassium….). ORGANIZATION. About 206 bones
Bones are made of OSSEOUS TISSUE
Support and Protection
Blood cell formation (bone marrow) - hemopoiesis
Storage of inorganic materials (salt, calcium, potassium….)
About 206 bones
2 Main Divisions – Axial & Appendicular
Head, neck, trunk
Thoracic Cage (ribs, 12 pairs)
Medullary Cavity – hollow chamber filled with bone marrow
Red Marrow (blood)
Yellow Marrow (fat)
– lining of the medullary
Compact (wall of the diaphysis)
Spongy (cancellous, epiphysis) - red marrow
– Coloring of a Long Bone
Matching quiz at http://www.mhhe.com/biosci/ap/holehaap/student/olc2/chap07matching01.html
MATRIX - where the bone cells live
OSTEOCYTES - mature bone cells, enclosed in tiny chambers called LACUNAE
OSTEOCYTES form rings (LAMELLAE) around a HAVERSIAN CANAL which houses blood vessels
Osteocytes are linked by CANALICULI
Haversian Canals are linked by VOLKMAN's CANALS
ALL BONES START AS HYALINE CARTILAGE, areas graduallly turn to bone
PRIMARY OSSIFICATION CENTER (shaft)
SECONDARY OSSIFICATION CENTER (ends)
EPIPHYSEAL DISK (growth plate) is a band of cartilage between the epiphysis and diaphysis
These areas increase bone length as the cells ossify
Cartilage becomes OSTEOBLASTS become OSTEOCYTES
OSTEOCLASTS - dissolve bone tissue to release minerals, process is called RESORPTION
* Assignment - Coloring of the Aging Hand
Types of Joints
1. Ball and Socket
1. Frontal -2. Parietal - 3. Occipital -4. Temporal - 5. Sphenoid - 6. Maxilla - 7. Mandible -
8. Zygomatic -
Foramen - refers to any tiny opening, nerves and blood vessels leave this opening to supply the face
Fissure - any wide gap between bones
1. Coronal - between frontal and parietal bones2. Lambdoidal - between occipital and parietal bones3. Squamosal - between temporal and parietal bones4. Sagittal - between parietal bones
* Assignment: Skull Labeling
Neck = cervical
Middle Back = thoracic
Lower Back = lumbar
Ulna goes to pinky (P-U)
Radius goes to thumb
*extra credit opportunity
Assignment – Skeleton Labeling
BONE SPURS: abnormal growth. Can occur on any bone (e.g. heel).
OSTEOPOROSIS: Increased activity of osteoclasts cause a break down bone, and the subsequent fewer minerals in the extracellular matrix make it fragile. The spongy bone especially becomes more porous.
Men get it as well as women. What’s the best way to prevent osteoporosis? Exercise! What does exercise do? Makes bones bigger.
The most common bone used for a bone graft is the iliac bone of the hip.
ABNORMALITIES OF THE SPINE
SCOLIOSIS is a lateral curve in the spine
KYPHOSIS is a hunchback curve
LORDOSIS is a swayback in the lower region.
ANKYLOSIS is severe arthritis in the spine and the vertebrae fuse.
Babies are born with 300 bones, but by adulthood we have only 206 in our bodies.
The giraffe has the same number of bones in its neck as a human: seven in total.
The long horned ram can take a head butt at 25 mph. The human skull will fracture at 5mph.