1. Science Starter How many bones are there in the human body?
Be sure your “Mystery of the Bones” skeleton is turned in & completed
Science Starter
How many bones are there in the human body?
What is a “soft spot” in a baby?
Why are our joints important?
How many different joints do you think you have in your body?

2. Today’s Agenda Science Starter What does it mean to be double-jointed?
Types of Joints
Joints Worksheet
Whack-a-Bone
Exit Quiz

3. What does it mean to be Double-Jointed?
Some genetic basis
Medical term is “hypermobility” (no double/extra joint)

4. Ehlers Danlos Syndrome

5. Unit 4: Skeletal & Muscular System 4.2 Joints

6. Places where 2 (or more) bones meet
I. What are Joints?
Places where 2 (or more) bones meet
Bones are joined by more flexible connective tissue
Main connection types
Ligaments: “strings” that connect bone to bone
Cartilage: Provides cushioned, smooth surface for bones to contact each other

7. II. Types of Joints
Fibrous: Joined by tough connective tissue, not moveable
E.G: Skull fissures
Cartilaginous: Joined directly by cartilage, slightly moveable
E.G: Vertebral disks
Synovial (contains fluid-filled space, moveable)
E.G: Knees, shoulders, and more

8. III. Basic Motions at joints
Flexion: Decreasing angle of joint
Extension: Increasing angle at joint
Rotation: Movement of bone around longitudinal axis
Abduction: Moving bone laterally (away from body midline)
Adduction: Moving bone medially (toward midline)
Circumduction: Moving distal end of bone in a circle while proximal end stays in place (combination)

9. IV. Synovial Joints
Synovial Fluid- fluid within the joints that helps to lubricate

10. A. Ball and Socket
Structure: A ball (round) fits into a concave socket
Movements allowed: Circumduction
Examples: Shoulders, hips

11. B. Hinge
Structure: A cylinder fits into a notch
Movements: Flexion and extension only
Examples: Fingers, toes, elbows, knees

12. C. Pivot
Structure: A cylindrical post fits into a cylindrical space
Movements: Rotation
Examples: Radioulnar joints (allow lower arm to rotate)

13. D. Saddle
Structure: A C-shaped bone fits over a saddle- shaped bone
Movements: Flexion, extension, abduction, adduction
Examples: Base of thumb

14. E. Condyloid (ellipsoidal)
Structure: Ellipsoid, bone rests in concave cavity
Movements: Circumduction, but limited
Examples: Attachment of wrist to arm

15. F. Gliding
Structure: Flat bones sit atop one another
Movements: Bones slide past one another (flexion and extension)
Examples: Joints between carpals

16. Joint Worksheet Use your notes and the book to complete the worksheet
Anything you don’t complete will be homework
This will be checked tomorrow at the beginning of class
If you finish early, grab a laptop and go to my website to check out “Whack-a-bone”. See who is the fastest in your group!

17. / Ligament
Synovial Fluid

18. Exit Quiz What are the 2 connection types for joints?
What are the 6 types of synovial joints?
What joint type is in the top picture?
What movement type is in the bottom picture?