The Lungs and Bronchial Tree

What is the main function of the lungs?

Gas exchange, also known as respiration.

What is the difference between the right and left lungs?

The right lung is shorter and bulkier than the left lung.

How are the different lobes of the lungs separated?

Thin walls of tissue called "fissures" separate the different lobes.

How many lobes does the right lung have?

Has three lobes.

How many lobes does the left lung have?

Has two lobes.

What are bronchopulmonary segments?

Each lobe contains several these, which are served by their own vein and artery.

What is bronchopulmonary disease often confined to?

Few of the bronchopulmonary segments.

What are lobules in the lung?

Hexagonal in appearance and structure, served by a large bronchiole and its branches.

What happens to the connective tissue that separates lobules in smokers?

In smokers, the connective tissue separating individual lobules becomes blackened with carbon.

What does pulmonary circulation do?

Pulmonary arteries transfer oxygen-depleted blood, which is then oxygenated and transferred by pulmonary veins back to the heart.

How does pulmonary circulation return oxygenated blood to the heart?

Via the hilum and corresponding bronchi.

What is the role of bronchial circulation?

Provides oxygenated blood to systemic tissues and supplies low volume, high-pressure blood to all lung tissues except the alveoli.

What is the bronchial tree?

Where respiratory zone structures are located. The trachea divides into the right and left main bronchus.

What does each bronchus divide into?

Lobar bronchi, each supplying one lung lobe.

What are bronchioles?

Smallest branches of the bronchi.

What changes occur as the bronchi become smaller?

Cartilage rings are replaced by plates of irregular cartilage, mucosal epithelium thins, and smooth muscle increases.

What defines the respiratory zone of the lungs?

By the presence of thin-walled air sacs and is involved in the exchange of gases.

What structures make up the respiratory zone?

Respiratory bronchioles, alveolar ducts, and alveoli.

What is the function of the respiratory zone?

Allows inhaled oxygen to diffuse into lung capillaries in exchange for carbon dioxide.