1. Skeletal System Functions: 1) Supports body
2) Protects internal organs
3) Provides for movement
4) Stores mineral reserves
5) Provides a site for blood cell formation

2. Skeletal System Has 206 bones Divided into two sections:
1) Axial: skull, vertebral column, ribs, and
sternum
2) Appendicular: all other bones

3. Structure of Bones Bones are living tissue!!
Periosteum – tough layer of connective tissue surrounding bone
Compact bone – beneath the periosteum (dense but not solid)
Haversian canals– tubes that run through compact bone and contain blood vessels and nerves

4. Structure of Bones Spongy bone – inside outer layer of compact bone
Osteocytes – digest away old bone
Osteoclasts – maintain healthy bone
Osteoblasts – make new bone

6. 3-D Section of Bone Tissue

7. Bone Homeostasis
1.Most of our skeleton is constantly being broken down, and built back up
2.Amount of bone built up = amount of bone broken down
3.This balance of breakdown and buildup is called bone homeostasis

8. Bone marrow – soft tissue center of bone
Maintains the balance of minerals
Serves as a storage for minerals (Ca, P)
Two Types:
1) Yellow – made mostly of fats, aids in Red Blood Cell (RBC) production
2) Red – produces RBCs, white BC, and cells to help clotting

9. Skeletal Development The skeleton of the embryo is made of cartilage
Bone begins to replace cartilage by 9th week of development (known as ossification)

10. Joints Joints – where two or more bones meet Most allow movement
Some are fixed (no movement): skull

11. Pelvis, Sexual Dimorphism

12. Types of Joints Five types:
Ball and socket: allows rotational movements (shoulder, hip)
Ball and Socket Movement

13. Types of Joints, Cont’d
2) Pivot: bones twist against each other (atlas and axis of your vertebrae)
Pivot Joint in Arm

14. Types of Joints Cont’d
3) Hinge: back and forth movements much like a door (elbow, knee)

15. Types of Joints 4) Gliding: bones slide against each other (wrist)
5) Saddle: Freely moveable joint found only in the thumb

16. Joint support Ligaments: bands of tissue that connect bone to bone
Surrounds joints with wide range of motion and little skeletal support
Cartilage: covers bone ends and allows for smooth movement. Can also be found in joint to provide cushion (meniscus)
Bursa: sacs of fluid that act as shock absorbers
Tendons: bands of tissue that connect muscle to bone (patella tendon, Achilles)

17. Problems with Skeletal System - Breaks
Complete/Incomplete (Greenstick)
Displaced
Simple/Compound (breaks skin)
Impacted or Comminuted
Spiral
Hairline

18. Breaks - Complete & Displaced

19. Breaks - Incomplete/Greenstick

20. Breaks - Spiral

21. Breaks - Compound

22. Breaks - Comminuted

23. Breaks - Hairline

24. Osteoporosis

25. Problems with Skeletal System -Rheumatoid arthritis
Inflammation in joints
Redness, warmth, swelling, pain, fatigue
Occurs on both sides of body
Genetic, environmental, hormonal factors; immune system attacks the joints and other organs

26. Rheumatoid arthritis

27. Problems with Skeletal System - Dislocation
Normal Dislocated

28. Dislocation
Normal Dislocated