The lungs

Question 1

What covers the lungs?

Answer 1

Each lung is surrounded by a pleura cavity, which is formed by the visceral and parietal pleura.

Question 2

What are the left and right lung in close contact to?

Answer 2

Left lung

• Heart
• Oesophagus
• Arch of aorta
• Thoracic aorta

Right lung

• Heart
• Oesophagus
• Superior and Inferior Vena Cava
• Azygous vein

Question 3

Which of the two lungs is smaller and why?

Answer 3

The left lung is smaller due to the presence of the heart.

Question 4

How many lobes do the right and left lung have?

Answer 4

Right - 3 lobes - Superior, Middle and Inferior

Left - 2 lobes

Question 5

What is an oblique and horizontal fissure?

Answer 5

Oblique - Runs from inferior border of the lung in a superoposterior direction
Horizontal - Runs horizontally from the sternum, at the level the 4th rib until it meets the oblique fissure

Question 6

What are the three surfaces of the lungs?

Answer 6

Mediastinal - faces the lateral aspect of the middle mediastinum, The HILUM is on this surface.
Diaphragmatic (base) - rests on dome of diaphragm and has a concave surface
Costal - smooth and convex, faces internal surface of the chest wall.

Question 7

Why is the concavity of the right lung deeper than the left?

Answer 7

Because of the presence of the liver on the right side, the dome of the diaphragm is higher, therefore the concavity is higher

Question 8

What are the three borders of the lungs?

Answer 8

Anterior - formed by convergence of mediastinal and costal surfaces. Left lung has the cardiac notch.
Inferior - Separates base of lung from costal and mediastinal surfaces.
Posterior - smooth and rounded, formed by costal and mediastinal surfaces meeting posteriorly

Question 9

What is contained in the lung root?

Answer 9

1. A bronchus
2. Pulmonary artery
3. Two pulmonary veins
4. Bronchial vessels
5. Pulmonary plexus of nerves and lymphatic vessels

Question 10

How do the structures of the lung root enter and leave the lung

Answer 10

Through the lung hilum

Question 11

What is the brachial tree?

Answer 11

Passages that supply air to the alveoli of the lungs

Question 12

Which bronchus is a sweet likely to go down if you choke?

Answer 12

The right as it is wider and more vertical

Question 13

Describe the course of the bronchi

Answer 13

Each bronchus enters the lung via hilum, inside the lung they divide to form lobar bronchi (one to each lobe). Each lobar bronchus divides into several tertiary segmental bronchi. The segmental bronchi lead into conducting bronchioles which will become terminal bronchioles.

Question 14

What supplies the lungs

Answer 14

deoxygenated blood enters lungs via pulmonary artery and leaves lungs via 4 pulmonary veins (2 for each lung)

Question 15

How do the bronchi, lung roots and visceral pleura get their blood supply from?

Answer 15

Bronchial arteries from descending aorta.

Question 16

Where do the lungs drain?

Answer 16

Right - Azygous vein

Left - Accessory Hemiazygous vein

Question 17

Explain the nerve supply of the lungs

Answer 17

Derived from pulmonary plexus.

1. Parasympathetic - derived from vagus nerve, stimulate secretion form bronchial glands, contraction of bronchial smooth muscle and vasodilation of pulmonary vessels
2. Sympathetic - Derived from sympathetic trunks, relaxation and vasoconstriction
3. Visceral afferent - Conduct pain impulses to sensory ganglion of the vagus nerve.