1. Learning Target: Skeletal System
I Can… Describe the general function and organization of the skeletal system.
I Will…
List the components & Describe the functions of the skeletal system
Classify the different types of bones by shape and composition
Classify different types of joints by composition & movement
Describe the two main divisions of the skeletal system
Ch. 33.1, pp

2. Learning Target: Skeletal System
The components of the human skeletal system:
Bones
Calcification process of combining protein collagen and calcium phosphate
Cartilage
Flexible connective tissue found between your bones that cushions bones and allows for smooth movement
Ligaments
Long flexible bands of connective tissue that connect two bones across a joint
Joint – place where two bones meet allowing for different ranges of movement

3. Learning Target: Skeletal System
Where the femur and tibia meet form the knee joint.

4. Learning Target: Skeletal System
Functions of the Skeletal System:
Structure and support
Framework of the body
Protects internal organs
e.g. cranium, vertebrae, ribs
Resource storage of calcium
Ca2+ necessary for many body processes
Nerve conduction, muscle contraction, blood clotting
Attachment point for muscles
Movement
Makes blood cells (bone marrow)
Hematopoiesis
Learning Target: Skeletal System

5. Learning Target: Skeletal System
Hematopoiesis – production and specialization of blood cells in the bone marrow from multipotent hematopoietic stem cells.

6. Learning Target: Skeletal System
Bone Classification by Shape:
Long
Longer than wide
All bones of the limbs except wrist and ankle bones e.g. humerus, femur
Short
Cube-shaped
e.g. Wrist and ankle bones
Flat
Thin, flat and curved; like a “bone sandwich” (Compact – Spongy- Compact)
e.g. cranial, sternum

7. Learning Target: Skeletal System
Bone Classification by Shape:
Irregular
Irregular prominences / shape
e.g. vertebrae (pl.) vertebra (s)
Special Category (not by shape)
Sesamoid
Bone that develops within a tendon
Shaped like a sesame seed
e.g. knee cap or patella

8. Learning Target: Skeletal System
Bone Classification by Shape:
Learning Target: Skeletal System

9. Learning Target: Skeletal System
Bone Classification by Composition:
Compact bone and Spongy bone

10. Learning Target: Skeletal System
Bone Classification by Composition:
Compact bone – hard and dense

11. Learning Target: Skeletal System
Bone Classification by Composition:
Spongy bone – porous; holds and protects marrow

12. Learning Target: Skeletal System
Bone Formation:
Endochondral – flexible hyaline cartilage becomes bone

13. Learning Target: Skeletal System
Bone Formation:
Intramembranous –
Forms within fibrous connective membrane
All flat bones

14. Learning Target: Skeletal System
Skeletal joint – area where two bones meet and allow for different degrees of movement
Classified by type and degree of movement
Fibrous synarthrotic joints
Immovable
e.g. Teeth in jaw
e.g. Cranial bones
Cartilaginous amphiarthrotic joints
Allow partial movement
e.g. Discs between vertebrae
e.g. Breastbone/sternum and ribs
Learning Target: Skeletal System

15. Learning Target: Skeletal System
Synovial joints
Most movable
Cushioned by cartilage
Held together by ligament
Gliding joints – allows flat surfaces to slide over each other.
Ankle, Wrist

16. Learning Target: Skeletal System
Pivot joints –Two bones turn on each other allow rotation
Radius and ulna, axis & atlas
Learning Target: Skeletal System
It’s time to Move It
Saddle joints – Allows bone to move front to
back and left to right.
a) Thumb

17. Learning Target: Skeletal System
Hinge joints – Allows bone to move in one
plane direction back and forth
Knee, elbow
Learning Target: Skeletal System
Ball-and-socket joints – Allows bone to move
most freely; front and back, side to side and
circumduction (circle).
a) Shoulder, Hip

18. Learning Target: Skeletal System
Two Main Divisions of the Skeletal System:
Axial (80 bones)
Axis – Central line around which a body rotates
Bones of the Head, Neck, Back, and Trunk (chest)
Supports the weight of the body
Protects internal organs
Fibrous synathrotic and cartilaginous amphiarthrotic joints
Appendicular (126 bones)
Appendages – attachments to the main body
Bones of the arms and legs along with their attachment points
Allows the body to move
Synovial diarthrotic joints
Learning Target: Skeletal System
Babies are born with over 300 bones due to the cartilage nature of the unfused bones. But, as the individual becomes an adult and calcification and fusion of bones occurs, the over all number of bones reduces to 206.

19. Learning Target: Skeletal System
Axial Skeleton
Appendicular Skeleton

20. Learning Check: Skeletal System
What are the components of the skeletal system?
List the functions of the skeletal system.
Name five different types of bones categorized by shape.
Name two types of bone tissue.
Name two processes of ossification.
Classify joints by composition.
Classify and describe joints by movement.
Name the two divisions of the skeletal system & describe their function.