Joints (part of lecture 3)

Question 1

Name the big 3 joint classifications.

Answer 1

• Synarthrosis (Fibrous): “Immoveable”
• Amphiarthrosis (Cartilagenous): “Slightly moveable”
• Diarthrosis (Synovial): “Freely moveable”

Question 2

What are the 3 subclassifications of Synarthrosis Fibrous joints?

Answer 2

1) Suture (btwn skull bones)
2) Syndesmosis (e.g. btwn radius/ulna)
3) Gomphosis (teeth: twn tooth/socket)

Question 3

What are the 2 subclassifications of Amphiarthrosis Cartilagenous joints?

Answer 3

1) Symphysis (pubic, spine)
2) Synchondrosis (btwn ribs/sternum)

Question 4

What are the characteristics of Diarthrotic Synovial joints?

Answer 4

• Joint capsule
• Articulating surface
• Articular cartilage
• Synovial membrane
• Synovial fluid

Question 5

Name the 6 types of Diarthrosis Synovial joints.

Answer 5

1) Arthrodial (Gliding)
2) Ellipsoidal (Condyloid)
3) Ginglymus (Hinge)
4) Sellar (Saddle)
5) Enarthrodial (Ball-and-Socket)
6) Trochoid (Pivot)

Question 6

Diarthrosis Synovial: Describe Arthrodial joints.

Answer 6

(Gliding)
- Biaxial or triaxial
- e.g. carpal, tarsal joints

Question 7

Diarthrosis Synovial: Describe Ginglymus joints.

Answer 7

(Hinge)
- Uniaxial
- e.g. btwn humerus and ulna (elbow), fingers

Question 8

Diarthrosis Synovial: Describe Trochoid joints.

Answer 8

(Pivot)
- Uniaxial
- e.g. btwn head of radius + radial notch of ulna (forearm rotation)

Question 9

Diarthrosis Synovial: Describe Ellipsoidal joints.

Answer 9

(Condyloid)
- Biaxial
- e.g. btwn radius + scaphoid + lunate

Question 10

Diarthrosis Synovial: Describe Sellar joints.

Answer 10

(Saddle)
- Biaxial
- e.g. thumb (btwn trapezium + metacarpal of thumb)

Question 11

Diarthrosis Synovial: Describe Enarthrodial joints.

Answer 11

(Ball-and-socket)
- Triaxial
- e.g. shoulder, hip

Question 12

Lever systems: How is human mvmt caused?

Answer 12

by long bones, joints connecting them, and muscles crossing these joints

Question 13

What are the 4 components of a lever system?

Answer 13

1- A rigid body to use as a LEVER
2- A FULCRUM around which the lever moves
3- A FORCE applied to the lever to cause MOTION
4- A FORCE applied to the lever that gives RESISTANCE

Question 14

How to the 4 components of a lever system show up in the human body?

Answer 14

• Long bones: lever
• Joints: Fulcrum
• Muscles: moving force
• Gravity/weight: moving/resistive force

Question 15

Describe a 1st class lever.

Answer 15

• Fulcrum in btwn moving force (muscle) and resistance (weight)

(e.g., your neck keeping your head up)

Question 16

Describe a 2nd class lever.

Answer 16

• Resistance btwn fulcrum and force

(e.g., a calf raise)

Question 17

Describe a 3rd class lever.

Answer 17

• force in btwn fulcrum and resistance

(most abundant)
(e.g., flexing biceps)