Lecture 17 - Anatomy of Breathing

Question 1

Describe the lobes and fissures of the right lung

Answer 1

3 lobes (superior, middle, inferior), 2 fissures (one horizontal, one oblique)

Question 2

Describe the lobes and fissures of the left lung

Answer 2

2 lobes (superior, inferior), 1 fissure (oblique)

Question 3

What are the three named (“directional?”) surfaces of the lungs

Answer 3

Costal (adjacent to ribs), diaphragmatic (sits on the diaphragm), mediastinal (faces mediastinum)

Question 4

What is the name of the structure where the pulmonary vessels, bronchi, bronchial vessels, lymphatics and nerves enter/leave the lung?

Answer 4

Hilum

Question 5

Name and describe the 2 important physical properties of the lungs

Answer 5

Compliance - The ability of the lungs to expand (to let air in)
Elasticity - Elastic tissue allows lung expansion during inspiration and recoil during exhalation

Question 6

Name and define the two layers of pleura

Answer 6

Parietal - adheres to thoracic wall and diaphragm
Visceral - adheres to the lungs

Question 7

Name the three components of the sternum/breastbone

Answer 7

Manubrium, Body, Xiphoid Process

Question 8

Name the parts of a rib

Answer 8

Head, tubercle, shaft

Question 9

Which direction do the intercostal muscles run?

Answer 9

External - forwards and downwards
Internal - backwards and downwards

Question 10

Which nerve innervates the diaphragm?

Answer 10

Phrenic Nerve

Question 11

Which process alters the VERTICAL diameter during ventilation?

Answer 11

Contraction and Relaxation of the diaphragm

Question 12

Which process alters the AP (Anteroposterior) and TRANSVERSE diameter during ventilation?

Answer 12

Elevation of the ribs (at the sternal end)

Question 13

Which muscles are involved in quiet inspiration?

Answer 13

Diaphragm and the external intercostals

Question 14

Which muscles are involved in quiet expiration?

Answer 14

None - it is a passive process

Question 15

Which muscles are involved in forced inspiration?

Answer 15

(In addition to diaphragm + EICs) Pectoralis major and minor; Scalenes; Serratus Anterior; Sternocleidomastoid

Question 16

Which muscles are involved in forced expiration?

Answer 16

Internal and innermost intercostals (depress the ribs); abdominal muscles (compress the abdomen and force diaphragm upwards)