The Thorax

Question 1

What connects ribs to the sternum?

Answer 1

Costal cartilage

Question 2

What are the three parts of the sternum?

Answer 2

• manubrium
• body
• xiphoid process

Question 3

What is the role of the clavicle?

Answer 3

Attaches the upper limb to the axial skeleton, forming part of the upper limb girdle

Question 4

What directions do the lugs move for

1) inflation and 2) deflation

Answer 4

1) up

2) down

Question 5

How does the downward action of the ribs deflate the lungs during expiration?

Answer 5

puts pressure on the lungs causing them to deflate

Question 6

What joint is related to the expiration and inhalation of the lungs?

Answer 6

costovertebral joints (posterior aspect of bony thorax)

Question 7

what muscle causes the ribs to lift during inhalation?

Answer 7

external intercostal muscles

Question 8

Are the external intercostal muscles deep or superficial to the internal intercostal muscles?

Answer 8

Superficial

Question 9

What are the attachment points of the external intercostal muscles?

Answer 9

superior to inferior rib

Question 10

What muscle causes the ribs to depress?

Answer 10

internal intercostal muscles

Question 11

What are the attachment points of the internal intercostal muscles?

Answer 11

inferior to superior rib

Question 12

What are the muscles of the ribs innervated by?

Answer 12

intercostal nerves

Question 13

Where is the thoracic diaphragm located?

Answer 13

attaches to the costal margin (edge of rib cage) and lumbar vertebrae to the central tendon to separate thoracic and abdominal cavities

Question 14

What is the innervation of the diaphragm?

Answer 14

phrenic nerve

Question 15

What does contraction of the diaphragm cause?

Answer 15

flattening of the diaphragm as it is pulled down within its cavity

Question 16

What does the actions of the diaphragm cause?

Answer 16

space change to open or close the lungs

Question 17

explain the difference between quiet vs. forced expiration

Answer 17

active exhalation can be achieved by contraction of the abdominal wall muscles (rectus abdominus, transverse abdominus, external oblique muscle and internal oblique muscle). These press the abdominal organs upward into the diaphragm, reducing the volume of the thoracic cavity.
Quiet exhalation has little muscle contraction involved