The Effects of Lung Disease

Question 1

What is tidal volume?

Answer 1

The volume of air in each breath

Question 2

What is ventilation rate?

Answer 2

Number of breaths per minute

Question 3

What is forced expiratory volume (FEV1)

Answer 3

The maximum volume of air that can be breathed out in 1 second

Question 4

What is forced vital capacity (FVC)?

Answer 4

The maximum volume of air it is possible to breathe forcefully out after a deep breath in

Question 5

Give 4 examples of lung disease

Answer 5

1. Pulmonary tuberculosis
2. Fibrosis
3. Asthma
4. Emphysema

Question 6

Explain pulmonary tuberculosis

Answer 6

1. When infected with TB, immune system cells build a wall around bacteria in the lungs, forming tubercles
2. Infected tissue in the tubercle dies, gaseous exchange surface is damaged, tidal volume is decreased
3. TB causes fibrosis
4. Reduced tidal volume means less air can be inhaled with each breath so patients breath faster

Question 7

What are the symptoms of TB?

Answer 7

Persistent cough, coughing up blood and mucus, chest pains, shortness of breath and fatigue

Question 8

Explain fibrosis

Answer 8

1. Fibrosis is the formation of scar tissue in the lungs
2. Scar tissue is thicker and less elastic than normal lung tissue
3. Lungs are less able to expand so can’t hold as much air, tidal volume and FVC are reduced
4. There’s a reduction in the rate of gaseous exchange - diffusion is slower over thicker scarred membrane
5. Fibrosis sufferers have a faster ventilation rate than normal

Question 9

What are the symptoms of fibrosis?

Answer 9

Shortness of breath, a dry cough, chest pain, fatigue and weakness

Question 10

What is asthma?

Answer 10

A respiratory condition where the airways become inflamed and irritated

Question 11

What happens during an asthma attack?

Answer 11

1. The smooth muscle lining the bronchioles contracts and a large amount of mucus is produced
2. This causes constriction of the airway. Air flow in and out the lungs is severely reduced, less O2 enters the alveoli and moves into the blood. FEV1 is severely reduced

Question 12

What are the symptoms of asthma?

Answer 12

Wheezing, a tight chest, shortness of breath

Question 13

What is emphysema?

Answer 13

A lung disease caused by smoking or long-term exposure to air pollution

Question 14

Explain emphysema

Answer 14

1. Foreign particles get trapped in the alveoli
2. This causes inflammation, which attract phagocytes to the area. These produce an enzyme that breaks down elastin
3. Loss of elastin means the alveoli can’t recoil and expel air as well
4. It also leads to destruction of the alveoli walls, this reduces SA, so the rate of gaseous exchange decreases

Question 15

What are the symptoms of emphysema?

Answer 15

Shortness of breath and wheezing. Emphysema sufferers have an increased ventilation rate