Pectoral Muscles

Question 1

Pectoralis Major

Answer 1

O: medial 2/3 of clavicle, sternum, and costal cartilages 1-6

I: lateral lip of intertubercular groove (crest of greater tubercle) of humerus

A: adduction and medial rotation of the arm, flexion, and extension

In: medial and lateral pectoral nerves

Question 2

Pectoralis Minor

Answer 2

O: ribs 3-5

I: coracoid process of scapula

A: depression of the shoulder, downward rotation of scapula

In: medial pectoral nerve