1. Skeletal system
HCS 1050
SLOs – 1.6 – 1.12

2. Functions of the Skeletal system
Serve as a frame for the body
Protect organs
Serve as a lever for movement
Form blood cells
Store minerals

3. Functions:

4. Categorizing Bones Flat – ribs, cranium
Short – carpals of the wrist, tarsals of the ankle
Irregular – vertebrae, facial bones
Long – most of the skeleton including bones of the arms and legs

5. Flat bones

6. Short Bones

7. Irregular Bones

8. Long Bones

9. Structure and Significance of Long Bones
The long narrow shaft of long bones is called the diaphysis
At the center of the diaphysis is a medullary cavity which contains bone marrow
The two irregular ends are called the proximal and distal epiphysis

10. Long Bone Structure

11. Bone Marrow
Red marrow is found in the spongy bone at the ends of the long bones and at the center of other bones
Red marrow manufactures blood cells
Yellow marrow is found mainly in the central cavities of the long bones
Yellow marrow is composed of mainly fat

12. Bone Marrow

13. Bone Membranes and Cells
Bones are covered on the outside (except at the joint regions) by a membrane called the periosteum
This membrane’s inner layer contains cells (osteoblasts) that are essential in bone formation not only during growth but also in the repair of injuries.
Blood vessels in the periosteum help to nourish bone tissue

14. Bone Membranes and Cells
There are also nerve fibers here that register pain when a bone is fractured or when it is hit
The endosteum is a thin membrane that lines the bone’s marrow cavity and is also important in bone tissue growth and repair

15. Compact and Spongy Bone
Bone tissue or osseous tissue, is very much alive with their own blood vessels, lymphatic vessels and nerves
The two types of osseous tissue are:
1) Compact bone:
hard and dense
Makes up the main shaft of long bones and outer layer of other bones
2) Spongy bone:
Have more spaces than compact bone
Found at the epiphyses (ends) of long bones

16. Do Now!
Complete workbook pg. 101 handout exercises 7.1 and 7.2
Make sure to color the different structures on the diagram
Complete workbook pg. 102 handout exercises 7.3 – 7.5