3A - The effects of lung disease

Question 1

What can help to diagnose lung disease?

Answer 1

Measures of lung function.

Question 2

What do lung diseases affect?

Answer 2

Ventilation (breathing) and gas exchange in the lungs.

Question 3

What is tidal volume?

Answer 3

The volume of air in each breath.

Question 4

What is the average tidal volume between for adults?

Answer 4

Between 0.4dm3 and 0.5dm3.

Question 5

What is ventilation rate?

Answer 5

The number of breaths per minute.

Question 6

What is the avg ventilation rate?

Answer 6

15 breaths per minute.

Question 7

What is forced expiratory volume1 (FEV1)?

Answer 7

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

Question 8

What is forced vital capacity (FVC)?

Answer 8

The max volume of air it is possible to breath forcefully out of the lungs after a really deep breath in.

Question 9

What is pulmonary tuberculosis (TB)?

Answer 9

A lung disease where someone becomes infected with tuberculosis bacteria causing immune system cells to build a wall around the bacteria in the lungs forming small, hard lumps known as tubercles.

Question 10

What happens to tissue infected within tubercles and what happens because of this?

Answer 10

It dies and the gaseous exchange surface is damaged so tidal volume is decreased.

Question 11

What does tuberculosis cause and what does this cause?

Answer 11

Fibrosis which reduces the tidal volume.

Question 12

What does a reduced tidal volume mean happens?

Answer 12

Less air can be inhaled with each breath. in order to take in enough oxygen, patients have to breath faster - ventilation rate is increased.

Question 13

What are common symptoms of TB?

Answer 13

A persistent cough, coughing up blood and mucus, chest pains, shortness of breath and fatigue.

Question 14

What is fibrosis?

Answer 14

A lung disease where there is the formation of scar tissue in the lungs which is thicker and less elastic than normal lung tissue.

Question 15

What can fibrosis be the result of?

Answer 15

An infection or exposure to substances like asbestos or dust.

Question 16

What is the difference between scar tissue and normal lung tissue?

Answer 16

Scar tissue is thicker and less elastic than normal lung tissue.

Question 17

What does fibrosis mean happens?

Answer 17

The lungs are less able to expand and so can’t hold as much air as normal - tidal volume is reduced and so is FVC. There is a reduction in the rate of gaseous exchange as diffusion is slower across a thicker scarred membrane.

Question 18

What are symptoms of fibrosis?

Answer 18

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

Question 19

What do fibrosis sufferers have a faster rate of compared to usual and why?

Answer 19

A faster ventilation rate to get enough air into their lungs to oxygenate their blood.

Question 20

What is asthma?

Answer 20

A respiratory condition where the airways become inflamed and irritated.

Question 21

What are the causes of asthma?

Answer 21

Allergic reactions to substances such as pollen and dust.

Question 22

What happens during an asthma attack?

Answer 22

The smooth muscle lining the bronchioles contracts and a large amount of mucus is produced.

Question 23

What does the large amount of mucus being produced during an asthma attack cause?

Answer 23

Constriction of the airways, making it difficult for the sufferer to breath properly. Air flow in and out of the lungs is severely reduced, so less oxygen enters the alveoli and moves into the blood. This means that FEV1 is severely reduced.

Question 24

What are symptoms of asthma?

Answer 24

Wheezing, a tight chest and shortness of breath.

Question 25

How quick do symptoms come on during an asthma attack?

Answer 25

Suddenly.

Question 26

How can the symptoms of asthma be relieved?

Answer 26

By drugs (often in inhalers) which cause the muscle in the bronchioles to relax, opening up the airways.

Question 27

What is emphysema and what is it caused by?

Answer 27

A lung disease caused by smoking or long-term exposure to air pollution - foreign particles in the smoke (or air) become trapped in the alveoli.

Question 28

What does the air particles becoming trapped in the alveoli in emphysema cause?

Answer 28

Inflammation, which attracts phagocytes to the area. The phagocytes produce an enzyme that breaks down elastin (a protein found in the walls of the alveoli). This stops the alveoli recoiling to expel air as well so the air remains trapped in the alveoli.

Question 29

What does a loss of elastin in the alveolus of those with emphysema cause?

Answer 29

Alveoli to be unable to recoil to expel air as well so air remains trapped in the alveoli. It also leads to destruction of the alveoli walls, which reduces the surface area of the alveoli, so the rate of gaseous exchange decreases.

Question 30

What are symptoms of emphysema?

Answer 30

Shortness of breath and wheezing. Increased ventilation rate (to increase the amount of air - containing oxygen - reaching their lungs).

Question 31

What do TB, asthma and emphysema all reduce?

Answer 31

The rate of gas exchange in the alveoli.

Question 32

What is common in TB, asthma and emphysema?

Answer 32

There is a reduce rate of gas exchange in the alveoli so less oxygen is able to diffuse into the bloodstream so the body cells receive less oxygen and the rate of aerobic respiration is reduced. This means less energy is released and sufferers often feel tired and weak.