Muscles: Anterior Trunk:

Question 1

External Intercostal Muscles:

-Origin, Insertion and Action

Answer 1

Origin: Lower border of the ribs, within the intercostal space

Insertion: Onto the upper border of the ribs

Action: Assists in breathing

Question 2

Internal Intercostal Muscles:

-Origin, Insertion and Action

Answer 2

Origin: Upper border of the ribs, within the intercostal space

Insertion: Upper border of the ribs below it

Action: Assist in breathing

Question 3

Pectorals Major:

-Action

Answer 3

Flexion and retraction (adduction) of the shoulder

Question 4

Pectoralis Minor:

-Action

Answer 4

Depresses and protracts (abducts) the scapula

Question 5

External Oblique’s:

-Action

Answer 5

Compress/ rotate

Question 6

Internal Oblique’s:

-Action

Answer 6

Compresses/ rotate

-The deepest layer of the obliques wrap around the spine for protection/ stability

Question 7

Rectus Abdominis:

-Action

Answer 7

Flexion and Compression

-Right and left sides are separated by the Linea Alba, and are sectioned off by lines called Tendinous Inscriptions