2Nd Order Unit 3

Front 1

External Intercostals - Action

Back 1

elevate ribs during inhalation

Front 2

External Intercostals - Innervation

Back 2

thoracic spinal NN

Front 3

External Intercostals - Origin

Back 3

inferior border of superior rib

Front 4

External Intercostals - Insertion

Back 4

superior border of inferior rib

Front 5

Internal Intercostals - Action

Back 5

depress ribs during forced exhalation; antagonistic to external intercostals

Front 6

Internal Intercostals - Innervation

Back 6

thoracic spinal NN

Front 7

Internal Intercostals - Origin

Back 7

superior border of inferior rib

Front 8

Internal Intercostals - Insertion

Back 8

inferior border of superior rib

Front 9

Transversus Thoracis - Action

Back 9

depresses ribs during forced exhalation

Front 10

Transversus Thoracis - Innervation

Back 10

thoracic spinal NN

Front 11

Transversus Thoracis - Origin

Back 11

posterior surface of xiphoid process and inferior region of sternum

Front 12

Transversus Thoracis - Insertion

Back 12

costal cartilages 2-6

Front 13

Diaphragm - Action

Back 13

contraction causes flattening of diaphragm (moves inferiorly) and thus expansion of the thoracic cavity; increases pressure in abdominopelvic cavity

Front 14

Diaphragm - Innervation

Back 14

Phrenic N

Front 15

External Oblique - Action

Back 15

unilateral: lateral flexion and rotation of vertebral column

bilateral: flexes vertebral column, compresses abdominal wall, used in forced exhalation

Front 16

External Oblique - Innervation

Back 16

Spinal NN

Front 17

Internal Oblique - Action

Back 17

unilateral: lateral flexion and rotation of vertebral column

bilateral: flexes vertebral column, compresses abdominal wall

Front 18

Internal Oblique - Innervation

Back 18

Spinal N

Front 19

Transversus Abdominis - Action

Back 19

unilateral: lateral flexion of vertebral column

bilateral: flexes vertebral column, compresses abdominal wall, used in forced exhalation

Front 20

Transversus Abdominis - Innervation

Back 20

Spinal N

Front 21

Rectus Abdominis - Action

Back 21

flexes vertebral column, compresses abdominal wall, used in forced exhalation

Front 22

Rectus Abdominis - Innervation

Back 22

Spinal N

Front 23

Innermost Intercostal MM - Action

Back 23

depresses ribs during forced exhalation; antagonistic to external intercostals

Front 24

Innermost Intercostal MM - Innervation

Back 24

Thoracic Spinal N

Front 25

Subcostal M - Action

Back 25

depresses ribs during forced exhalation; antagonistic to external intercostals

Front 26

Subcostal M - Innervation

Back 26

Thoracic Spinal N

Front 27

Pyramidalis - Action

Back 27

tenses linea alba

Front 28

Pyramidalis - Innervation

Back 28

ventral spinal N

Front 29

Subclavius - Action

Back 29

stabilizes and depresses clavicle (accessory breathing m)

Front 30

Subclavius - Innervation

Back 30

Nerve to subclavius

Front 31

Pectoralis Minor - Action

Back 31

protracts and depresses scapula (accessory breathing m)

Front 32

Pectoralis Minor - Innervation

Back 32

medial pectoral N

Front 33

Serratus Anterior - Action

Back 33

agonist in scapula protraction; superiorly rotates and stabilizes scapula (accessory breathing m)

Front 34

Serratus Anterior - Innervation

Back 34

Long thoracic N

Front 35

Levator Costarum - Action

Back 35

elevates ribs (accessory breathing m)

Front 36

Levator Costarum - Innervation

Back 36

intercostal N

Front 37

Pectinate M - Action

Back 37

helps right atrium dilate without much muscle stress

Front 38

Papillary M - Action

Back 38

contracts to prevent inversion or prolapse of AV valves on systole