pt 4: ch23 A

What are bronchopulmonary segments?

Independent subdivisions of a lung supplied by their own segmental bronchus and blood vessels.

How many bronchopulmonary segments are in the right lung?

10.

How many bronchopulmonary segments are in the left lung?

8–10.

Why are bronchopulmonary segments considered autonomous?

Each has its own bronchus, artery, vein, and lymphatic vessels.

Why are bronchopulmonary segments clinically important?

They can be surgically removed individually.

What are lung lobules?

Smaller subdivisions within bronchopulmonary segments.

What supplies each lobule?

A terminal bronchiole, arteriole, venule, and lymphatic vessel.

What is COVID-19?

A respiratory disease caused by SARS-CoV-2.

What are common symptoms of COVID-19?

Dry cough, fatigue, fever, and possible loss of smell or taste.

What is long COVID?

Persistent symptoms that remain after the initial infection.

How do mRNA vaccines work?

They instruct cells to produce a viral spike protein that triggers an immune response.

Why are mRNA vaccines effective?

They create immune memory that helps prevent severe disease.

What respiratory infections are associated with smoking?

Bronchitis, pneumonia, and other respiratory infections.

How does smoking affect lung tissue?

It causes cellular and genetic damage.

What chronic lung disease is strongly linked to smoking?

Emphysema.

What cancers are associated with smoking?

Lung, esophageal, stomach, and pancreatic cancers.

How does smoking affect blood vessels?

It promotes atherosclerosis.

How does smoking affect pregnancy?

It increases the likelihood of low birth-weight babies.

How does smoking affect oxygen delivery?

It decreases oxygen delivery to body tissues.

What health problems are associated with secondhand smoke?

Bronchitis, asthma, and ear infections.

What is lung cancer?

A highly aggressive cancer originating in respiratory epithelium.

Approximately what percentage of lung cancers are caused by smoking?

About 85%.

What are common symptoms of lung cancer?

Chronic cough, coughing up blood, excess mucus, and breathing difficulties.

What are the two blood circulations associated with the lungs?

Pulmonary circulation and bronchial circulation.

What is the purpose of pulmonary circulation?

To oxygenate blood and remove carbon dioxide.

What type of blood do pulmonary arteries carry?

Deoxygenated blood.

Where do pulmonary arteries deliver blood?

To pulmonary capillaries surrounding alveoli.

What happens to blood in pulmonary capillaries?

It becomes oxygenated.

Where does oxygenated blood travel after leaving pulmonary capillaries?

Into pulmonary veins.

To which heart chamber do pulmonary veins return blood?

The left atrium.

What is the function of bronchial circulation?

To supply oxygenated blood to lung tissues.

Where do bronchial arteries originate?

From the descending aorta.

How many bronchial arteries are usually present?

Three or four.

What do bronchial veins collect?

Deoxygenated blood from lung tissues.

Where does some bronchial venous blood drain?

Into pulmonary veins.

What is the function of lymphatic drainage in the lungs?

Removal of excess fluid and debris.

Where are lung lymphatic vessels located?

In connective tissue, around bronchi, and within pleura.

Why are lymph nodes important in the lungs?

They filter particles and pollutants not removed by cilia.

What is the pleura?

A serous membrane covering the lungs and lining the thoracic cavity.

What tissues form the pleura?

Simple squamous epithelium and areolar connective tissue.

What is the visceral pleura?

The pleural layer directly covering the lung surface.

What is the parietal pleura?

The pleural layer lining the thoracic cavity.

What surfaces are lined by parietal pleura?

Thoracic wall, mediastinum, and diaphragm.

Why does each lung have a separate pleural cavity?

To limit the spread of infection.

What is the pleural cavity?

The space between visceral and parietal pleura.

Why is the pleural cavity called a potential space?

The pleural layers nearly touch during normal lung inflation.

What fluid is found in the pleural cavity?

Serous fluid.

What is the function of pleural fluid?

Lubricates pleural membranes and reduces friction.

How much pleural fluid is normally present?

Less than 15 mL.

How is pleural fluid removed?

By lymphatic drainage.

What is pleurisy?

Inflammation of the pleural membranes.

What is the main symptom of pleurisy?

Sharp chest pain during breathing.

Why does pleurisy cause pain?

Inflamed pleural surfaces rub together causing friction.

Is pleurisy usually unilateral or bilateral?

Usually affects only one side.

What is pleural effusion?

Excess fluid accumulation in the pleural cavity.

What symptoms can pleural effusion cause?

Shortness of breath and chest pain.

What cardiac condition can cause pleural effusion?

Left-sided heart failure.

What vascular condition can cause pleural effusion?

Pulmonary embolism.

What liver condition can cause pleural effusion?

Cirrhosis.

What respiratory diseases can cause pleural effusion?

Lung infections and lung cancer.

What is pneumothorax?

Air accumulation in the pleural cavity.

What can cause an external pneumothorax?

A penetrating chest wound.

What can cause an internal pneumothorax?

Rib injury or rupture of an alveolus.

Why is pneumothorax dangerous?

It can equalize intrapleural and intrapulmonary pressures.

Can a small pneumothorax resolve on its own?

Yes.

Why is a large pneumothorax a medical emergency?

It can cause lung collapse and severe breathing impairment.

How is a large pneumothorax treated?

A tube is inserted into the pleural cavity to remove air.

What is atelectasis?

Collapse of a lung.

What commonly causes atelectasis in this chapter?

Equalization of intrapleural and intrapulmonary pressures due to pneumothorax.

What happens to the lung during atelectasis?

It remains collapsed until pressure is restored.

How is atelectasis corrected when caused by pneumothorax?

By removing air from the pleural cavity.

What is the difference between pulmonary and bronchial circulation?

Pulmonary circulation oxygenates blood, while bronchial circulation supplies oxygenated blood to lung tissues.

What is the difference between visceral and parietal pleura?

Visceral pleura covers the lungs; parietal pleura lines the thoracic cavity.

What is the difference between pleurisy and pleural effusion?

Pleurisy is inflammation of pleura; pleural effusion is excess fluid in the pleural cavity.

What is the difference between pneumothorax and atelectasis?

Pneumothorax is air in the pleural cavity; atelectasis is lung collapse resulting from pressure loss.

What structure carries deoxygenated blood to the lungs?

Pulmonary arteries.

What structure carries oxygenated blood from the lungs to the heart?

Pulmonary veins.

What is the major function of the pleural membranes?

Reduce friction and help maintain lung expansion.

What is the major function of alveoli?

Gas exchange between air and blood.

What is the major function of surfactant?

Prevent alveolar collapse during expiration.

What is the major function of alveolar macrophages?

Remove microorganisms and debris from alveoli.

What is the major function of the respiratory membrane?

Allow rapid diffusion of oxygen and carbon dioxide.

What is the major function of the bronchial tree?

Conduct air to and from the respiratory zone.

What is the major function of the conducting zone?

Transport, filter, warm, and humidify air.

What is the major function of the respiratory zone?

Gas exchange.