Muscle Origins, Insertions, & Actions

Question 1

Orbicularis oris

Answer 1

Action: Closes and protrudes lips for kissing
Origin: Surrounding the opening of the mouth
Insertion: The skin at the corner of the mouth

Question 2

Masseter

Answer 2

Action: Move the mandible (mastication) - Closes mouth
Origin: Maxilla and zygomatic arch
Insertion: Mandible

Question 3

Extraocular muscles Names

Answer 3

Superior and Inferior oblique, Superior and Inferior rectus, and medial and lateral rectus

Question 4

Extraocular Muscles

Answer 4

Action: rapid and precise movement of the eyes
Origin: Back of the orbit
Insertion: Different parts of eyeball

Question 5

Sternocleidomastoid (SCM)

Answer 5

Action: Flex and rotate head
Origin: Clavicle and sternum
Insertion: Mastoid process of the temporal bone

Question 6

Pectoralis Major

Answer 6

Action: Adducts and medially rotates arm at shoulder joint
Origin: Sternum and clavicle
Insertion: Proximal humerus

Question 7

Pectoralis Minor

Answer 7

Action: Internally rotates the shoulder
Origin: Ribs 3-5
Insertion: Coracoid process of the scapula

Question 8

Deltoid

Answer 8

Action: Abducts, flexes, and medially rotates the upper arm at the shoulder joint
Origin: Lateral clavicle and upper scapula
Insertion: Deltoid tuberosity on shaft of humerus

Question 9

Trapezius

Answer 9

Action: Supports arm and moves the scapula up, down, in and out
Origin: Occipital Bone and cervical spine
Insertion: Clavicle, scapula, and lower thoracic vertebrae

Question 10

Latissimus Dorsi

Answer 10

Action: Drives arm inferiorly and superiorly (swimmer’s muscles)
Origin: Thoracic and lumbar vertebrae and iliac bone
Insertion: Mid-humerus

Question 11

Rectus abdominus

Answer 11

Action: Flexes vertebral column and compresses abdomen
Origin: Pubic bone
Insertion: Ribs and sternum

Question 12

External oblique

Answer 12

Action: Flexes vertebral column and compresses abdomen
Origin: Ribs 5-12
Insertion: Iliac crest and linea alba

Question 13

Diaphragm

Answer 13

Action: Pulling down on lungs
Origin: Inferior 6 ribs (anteriorly) and lumbar vertebrae (posteriorly)
Insertion: Central tendon

Question 14

Biceps brachii

Answer 14

Action: Flexes and supinates forearm at elbow joint and flexes arm at shoulder joint
Origin: Scapula
Insertion: Radius

Question 15

Brachialis

Answer 15

Action: Flexor of forearm at elbow
Origin: Distal anterior surface of humerus
Insertion: Ulna

Question 16

Triceps brachii

Answer 16

Action: Extends forearm at elbow joint and arm at shoulder joint
Origin: Scapula and posterior surface of humerus
Insertion: Olecranon process of ulna

Question 17

Brachioradialis

Answer 17

Action: Supinates the forearm at the radioulnar joint
Origin: Humerus
Insertion: Distal radius

Question 18

Gluteus Maximus

Answer 18

Action: Extends and laterally rotates thigh at hip joint
Origin: Iliac crest, sacrum and coccyx
Insertion: Femur

Question 19

Quadricep Group Names

Answer 19

Rectus femoris, vastus lateralis, vastus intermedius, and vastus medialis

Question 20

Quadricep Group

Answer 20

Action: Flexes thigh at high joint and extends leg at knee joint
Origin: Iliac spine and proximal femur
Insertion: Patella and proximal tibia

Question 21

Hamstring Group Name

Answer 21

Biceps femoris, Semitendinosus, and Semimembranous

Question 22

Hamstring Group

Answer 22

Action: Flexing knee
Origin: Ischial tuberosity
Insertion: Proximal tibia and fibula

Question 23

Tibialis anterior

Answer 23

Action: Dorsiflexes and inverts the foot
Origin: Tibia
Insertion: First cuneiform and first metatarsal

Question 24

Gastrocnemius and soleus

Answer 24

Function as one often called the gastrocsoleus muscle
Action: plantar flex the foot at ankle joint (standing on tip toes)
Origin: Femur, capsule of knee, head of fibula
Insertion: Calcaneus by way of Achilles tendon

Question 25

Thenar

Answer 25

Lateral aspect of palm

Action: Oppose thumb against other 4 fingers

Question 26

Hypothenar

Answer 26

Medial aspect of palm

Action: Oppose thumb against other 4 fingers