Muscles lll

Question 1

Answer 1

Pectoralis Major

O: clavicle, sternum

I: Humerus below glenoid tubercle

A: Medially rotate humerus (hug)

Question 2

Answer 2

Pectoralis Minor

O: ribs 3-5

I: coracoid process

A: depresses scapula, “pick up pectoralis”

Question 3

Answer 3

Serratus Anterior

O: ribs 1-9

I: scapula (medial and inferior border)

A: abducts scapula (boxer’s muscle)

Question 4

Answer 4

Diaphragm

O: Xiphoid, ribs 5-12, L1-L5

I: central tendon (inserts into itself)

A: pulls central tendon down during inspiration

Question 5

Answer 5

External Intercostals

O: Lower margin of ribs

I: rib below

A: draws ribs up during inspiration

Question 6

Answer 6

Internal Intercostals

O: upper margin of ribs

I: rib above

A: draws ribs down during expiration

Question 7

Answer 7

Splenius Capitis

O: C7-T3 or T4

I: occipital and temporal bones

A: extend and rotate head at neck

Question 8

Answer 8

Sternocleidomastoid

O: sternum, clavicle

I: mastoid process

A: Flex neck

Question 9

Answer 9

Middle Scalene

O: C2-C7, posterior transverse process

I: 1st rib

A: elevates ribs 1-2 in inspiration, flex head laterally