Articulations & Actions

Question 1

What are the three structural types of joint?

Answer 1

Fibrous, cartilaginous, synovial.

Question 2

What are the three functional types of joint? Give an example of each.

Answer 2

Synarthroses, amphiarthroses, diarthroses.

Question 3

All joints with a “synovial” structural type have what kind of functional type?

Answer 3

Diarthroses

Question 4

Define the term “action” as it pertains to the muscular system.

Answer 4

Movement at the joint.

Question 5

Name the muscle action when a movement is described (e.g., nodding your head).

Answer 5

Moving the limb or hand laterally away from the body, or spreading the fingers or toes, is abduction.

Adduction brings the limb or hand toward or across the midline of the body, or brings the fingers or toes together.

Circumduction is the movement of the limb, hand, or fingers in a circular pattern. Turning of the head side to side or twisting of the body is rotation. Supination of the forearm turns the hand to the palm forward position, while forearm pronation turns the hand to the palm backward position.

Dorsiflexion of the foot at the ankle joint moves the top of the foot toward the leg, while plantar flexion lifts the heel and points the toes.

Eversion of the foot moves the bottom (plantar region) of the foot away from the midline of the body, while foot inversion faces the sole toward the midline.

Protraction of the mandible pushes the chin forward, and retraction pulls the chin back.

Depression of the mandible opens the mouth, while elevation closes it.

Opposition of the thumb brings the tip of the thumb into contact with the tip of the fingers of the same hand and reposition brings the thumb back next to the index finger.

Question 6

Give an example of fibrous structural type.

Answer 6

Sutures between the bones of the skull.

Question 7

Give an example of cartilaginous structural type.

Answer 7

intervertebral discs between the vertibra

Question 8

Give an example of synovial structural type.

Answer 8

Allows free movement from synovial fluid and is the most common joint of our body. The hip joint, shoulder joint, elbows, ankles.

Question 9

Give an example for Synarthroses function type.

Answer 9

tightly connected making the joint immobile. The joint between teeth and teeth sockets.

Question 10

Give an example for amphiarthroses function type.

Answer 10

Slightly movable, the pubic symphysis is a good example.

Question 11

Give an example for diarthroses function type.

Answer 11

Freely moveable, hip, shoulder, elbow, etc.