Question
click below
click below
Question
Normal Size Small Size show me how
KIN/Joints & Levers
Joint and lever basics.
Question | Answer |
---|---|
The 3 parts of the lever system. | 1. Fulcrum: point of movement (joint). 2. Resistance: weight or force. 3. Effort: force exerted to overcome resistance. |
Class 1 Lever | Balanced. Example: Scull balanced on the spinal column. |
Class 2 Lever | Power. "Wheelbarrow". Example: the lower body area needed for forward momentum. |
Class 3 Lever | Greatest movement. Range of motion, flexibility. Most common in the body. |
Joint | The point where bones meet and movement occurs. |
Classification of Joints: A. B. | A. Class by function. B. Class by structure. |
Class by Function: 1. 2. 3. | 1. Synarthrotic: no movement. 2. Ampiarthrotic: some movement. 3. Diarthrotic: free movement. |
Class by Structure: 1. 2. 3. | 1. Fibrous (synarthrotic). 2. Cartilaginous (ampiarthrotic). 3. Synovial (diarthrotic) |
Diarthrotic/Synovial Joints - 6 types: | 1. Hinge 2. Ball & Socket 3. Pivot 4. Ellipsoid/Condyloid 5. Saddle 6. Gliding |
Articular Cartilage | Glass-like covering protecting ends of bones from friction while the articulate. |
Fibrous Stratum | Tough fibrous structure that connects bones with eachother (fibrous capsule around joint). |
Synovial Stratum | Membrane: secretes a viscous fluid that lubricates the joint. |
Ellipsoid Joint | The oval-shaped end of one bone articulating with the elliptical basin of another. |
Hinge Joint | Just like the door lock and the bathroom at Whidbey. |
Pivot Joint | Like a donut rotating around a broom handle. |
Gliding Joint | Occurs between 2 flat surfaces. |
Saddle Joint | Modified ellipsod. Composed of convex and concave articulating surfaces (like 2 saddles). |