Review Chapter 8- Skeletal Muscles

Question 1

Action of Deltoid

Answer 1

Extends arm when the posterior portion contracts abducts the arm when the lateral portion contracts and flexes the arm (at shoulder joint)

Question 2

Action of extensor digitorum

Answer 2

Extends the phalanges

Question 3

Action of gastrocnemius

Answer 3

Plantar flexes at ankle joint and flexes leg at knee joint (works with soleus)

Question 4

Action of gluteus Maximus

Answer 4

Extends and laterally rotates thigh at the hip joint

Question 5

Action of latissimus dorsi

Answer 5

Posterior arm muscle that extends the arm at the shoulder

Question 6

Action of masseter

Answer 6

Main muscle that closes jaw

Question 7

Action of orbicularis oris

Answer 7

Puckers lips

Question 8

Action of rectus femoris

Answer 8

Only quadriceps muscle that flexes the thigh and extends leg

Question 9

Action of triceps brachii

Answer 9

Antagonist of biceps brachii. Extends forearm at elbow/ extends arm at shoulder.

Question 10

Action of zygomaticus major

Answer 10

Smiling :)

Question 11

Antagonist

Answer 11

Muscle that produces an effect opposite of the prime mover

Question 12

How muscles are named

Answer 12

Rectus- fibers parallel to midline
Tranverse- fibers perpendicular to midline
Minor- smallest of a set
Maximus- largest of a set 
Biceps- two headed origin
Triceps- three headed origin
Orbicularis- circle shape
Deltoid- triangle

Question 13

Insertion

Answer 13

The end of a muscle attached to the movable bone

Question 14

Origin

Answer 14

End of a muscle attached to the stationary bone

Question 15

Synergist

Answer 15

Muscle that helps the prime mover function more efficiently

Question 16

Action of biceps brachii

Answer 16

Flexes arm and forearm