Thorax / Acting on Thoracic Wall

Question 1

(O) External intercostal muscles

Answer 1

inferior border of the rib

Question 2

(I) External intercostal muscles

Answer 2

superior border of rib below

Question 3

(N) External intercostal muscles

Answer 3

intercostal nerves

Question 4

(A) External intercostal muscles

Answer 4

raise ribs during inspiration
Increases anteroposterior and transverse
diameters of the thorax

Question 5

(O) Internal intercostal muscles

Answer 5

inferior border of the rib

Question 6

(I) Internal intercostal muscles

Answer 6

superior border of rib below

Question 7

(N) Internal intercostal muscles

Answer 7

intercostal nerves

Question 8

(A) Internal intercostal muscles

Answer 8

lower ribs during expiration

Question 9

(O) Innermost intercostal muscles

Answer 9

adjacent ribs

Question 10

(I) Innermost intercostal muscles

Answer 10

adjacent ribs

Question 11

(N) Innermost intercostal muscles

Answer 11

intercostal nerves

Question 12

(A) Innermost intercostal muscles

Answer 12

assists external and internal intercostals

Question 13

(O) diaphragm

Answer 13

Xiphoid process
Lower 6 costal cartilages
1st 3 lumbar vertebrae

Question 14

(I) diaphragm

Answer 14

central tendon

Question 15

(N) diaphragm

Answer 15

phrenic nerve

Question 16

(A) diaphragm

Answer 16

Muscle of inspiration
Increases vertical diameter of the thorax
Assist in raising lower ribs

Question 17

(O) Levatores costarum

Answer 17

Tip of transverse process of C7

and T1-11 vertebrae

Question 18

(I) Levatores costarum

Answer 18

rib below

Question 19

(N) Levatores costarum

Answer 19

posterior rami of thoracic spinal nerves

Question 20

(A) Levatores costarum

Answer 20

Raises ribs

Inspiratory muscle

Question 21

(O) Serratus posterior superior

Answer 21

Lower cervical and upper

thoracic spines

Question 22

(I) Serratus posterior superior

Answer 22

upper ribs (2-5)

Question 23

(N) Serratus posterior superior

Answer 23

intercostal nerves

Question 24

(A) Serratus posterior superior

Answer 24

raises ribs

inspiratory muscles

Question 25

(O) Serratus posterior inferior

Answer 25

``` Lower cervical and upper thoracic spines (C7-T3) ```

Question 26

(I) Serratus posterior inferior

Answer 26

lower ribs (9-12)

Question 27

(N) Serratus posterior inferior

Answer 27

intercostal nerves

Question 28

(A) Serratus posterior inferior`

Answer 28

depresses ribs | expiratory muscle

Question 29

(O) Subclavius

Answer 29

1st costal cartilage

Question 30

(I) Subclavius

Answer 30

clavicle

Question 31

(N) Subclavius

Answer 31

Nerve to subclavius from | upper trunk of brachial plexus

Question 32

(A) Subclavius

Answer 32

Depresses clavicle and steadies this bone | during movements of the shoulder girdle

Question 33

(O) Scalene muscles

Answer 33

transverse process of C1-C6

Question 34

(I) Scalene muscles

Answer 34

1st and 2nd rib

Question 35

(N) Scalene muscles

Answer 35

Anterior: C4-C6 | Medius and Posterior: Anterior rami of cervical nerves

Question 36

(A) Scalene muscles

Answer 36

elevates 1st and second rib | laterally flexes and rotates cervical part of vertebral column

Question 37

(O) abdominal wall muscles (anterior)

Answer 37

```  Lower 8 ribs  Lumbar fascia  Iliac crest  Symphysis pubis  Pubic crest ```

Question 38

(I) abdominal wall muscles (anterior)

Answer 38

xiphoid process linea alba symphisis pubis

Question 39

(N) abdominal wall muscles (anterior)

Answer 39

lower 6 thoracic nerves; iliohypogastric and iliolingual nerves

Question 40

(A) abdominal wall muscles (anterior)

Answer 40

compresses abdominal contents; assists in forced expiration, defacation, parturition and vomiting