A2 Respiratory system

Question 1

Name the organ responsible for gas exchange in humans

Answer 1

Lung

Question 2

Where in the lungs does gas exchange take place?

Answer 2

Alveolus

Question 3

Describe the pathway taken by air as it travels to the alveolus

Answer 3

Mouth/nose

Trachea

Bronchus

Bronchiole

Alveolus

Question 4

Name structure A

Answer 4

Trachea

Question 5

Which gas diffuses into the blood in the alveoli?

Answer 5

Oxygen

Question 6

How is the alveolus adapted for its function?

Answer 6

Large surface area

Thin walls - one cell thick

Rich blood supply

Question 7

Name structure B

Answer 7

Bronchus

Question 8

Name structure C

Answer 8

Bronchiole

Question 9

What is the function of the pulmonary surfactant

Answer 9

Lowers the surface tension and prevents alveolar collapse

Question 10

Describe the process of inspiration

Answer 10

Diaphragm muscle contracts

Diaphragm moves downwards

External Intercoastal muscles contract

Rib cage moves out and up

Increases the volume of the thorax

Decreases the pressure in the thorax

Air moves into the lungs

Question 11

Describe the process of expiration

Answer 11

Diaphragm relaxes

Diaphragm moves into a domed position

Intercostal muscles relax

Rib cage moves down and in

Volume of thorax decreases

Pressure in thorax increases

Air is forced out of the lungs

Question 12

What is the function of the pleural membranes?

Answer 12

Surround the lungs and contain pleural fluid

Question 13

What is the role of the cartilage rings in the trachea

Answer 13

Keeps the trachea open

Question 14

What is the function of the cilia?

Answer 14

Waft the mucus upwards towards the top of the trachea

Question 15

Name the cells that produce mucus in the respiratory system.

Answer 15

Goblet cells

Question 16

What is the function of the mucus found in the respiratory system?

Answer 16

Sticky

Traps pathogen and particles in the air

Question 17

How thick is the alveolus wall?

Answer 17

One cell thick

Reduces the diffusion pathway

Question 18

What type of chemical is the pulmonary surfactant?

Answer 18

Phospholipid

Question 19

How is a steep concentration gradient maintained at the gas exchange surface?

Answer 19

Lungs continuously ventilated

Ensure high concentration of oxygen in the alveolus

Blood containing very little oxygen is continuously delivered to the alveolus

Question 20

Give the equation for pulmonary ventilation

Answer 20

Tidal volume x ventilation rate

Question 21

What can spirometry be used to measure?

Answer 21

Amount of air exhaled n one second

Total volume of air that can be exhaled in one forced breath

Question 22

Which lung diseases can spirometry be used to test for?

Answer 22

Asthma

Pulmonary fibrosis

Cystic fibrosis

COPD

Question 23

How is a spirometry test carried out?

Answer 23

Explain the procedure to patient

Gain consent

Patient seals lips round mouth piece

Start with period of quiet breathing in and out

Take deep breath and then exhale as hard as possible for 6 seconds

Rapid inhalation and forced exhalation used to assess airway obstruction eg asthma COPD

Repeat results

Question 24

What is the function of the pleural fluid?

Answer 24

Lubrication

Question 25

Asthma causes difficulty in breathing. What happens in the respiratory system to cause this difficulty in breathing?

Answer 25

Inflammation of the bronchioles Increases friction Decreases volume of air in alveolus

Question 26

Name the physiological test that can be used to diagnose/assess asthma

Answer 26

Peak flow Spirometry

Question 27

What are the symptoms of asthma?

Answer 27

Difficulty in breathing Wheezing sound when breathing Tight feeling in chest Coughing

Question 28

Describe in detail what happens in an asthma attack

Answer 28

Muscles in bronchiole wall contract Constricts the diameter of the bronchiole. Less air travels to the alveolus for gas exchange

Question 29

How is asthma treated?

Answer 29

Bronchodilators - relax muscles in walls Corticosteroid - reduce inflammation

Question 30

What causes asthma?

Answer 30

Localised allergic reaction Triggered by a variety of allergens

Question 31

Give the cause of tuberculosis

Answer 31

Bacterial infection Caused by Mycobacterium tuberculosis or Mycobacterium bovis

Question 32

Give the symptoms of pulmonary fibrosis

Answer 32

Shortness of breath Chronic dry cough Pain in the chest Weakness or fatigue

Question 33

How is TB spread from person to person?

Answer 33

Air borne transmission eg coughing sneezing

Question 34

How does TB affect the lungs?

Answer 34

Infection causes inflammation Tubercles formed Scarring reduces elasticity of the lungs Thickening of the epithelium

Question 35

Give the symptoms of TB

Answer 35

Persistent productive cough Tiredness Loss of appetite Fever Coughing up blood

Question 36

How is TB treated?

Answer 36

Antibiotic drugs Vaccination

Question 37

TB is more common in developing countries or poor living conditions. Why?

Answer 37

Lack of education for completing courses of drug treatment Cramped living condition Poor ventilation Poor health facilities Poor diet

Question 38

Which respiratory disease causes the epithelium of the alveoli to thicken?

Answer 38

Pulmonary fibrosis

Question 39

Which occupations can increase the incidence of pulmonary fibrosis?

Answer 39

Any job where particles are in the air Asbestos fibres - builders Coal dust - miners Grain dust - farmers Bird and animal droppings - farmer/zoo keeper

Question 40

What is the biggest cause of emphysema?

Answer 40

Smoking

Question 41

Give the symptoms of emphysema

Answer 41

Shortness of breath Shallow rapid breathing Chronic cough

Question 42

Which lung disease results in a loss of surface area of alveoli?

Answer 42

Emphysema

Question 43

Describe in detail how alveolus are destroyed in emphysema

Answer 43

Cigarette smoke stimulates white blood cells to release enzymes Enzymes break down walls of alveoli Loss of elasticity as elastin is broken down Reduces ability of lungs to reoil Air cannot be removed from the alveoli

Question 44

What does peak flow measure?

Answer 44

Rate that air can be exhaled by a person

Question 45

Give the units used in measuring peak flow

Answer 45

Litres per minute

Question 46

What does a pulse oximeter measure?

Answer 46

Oxygen level (saturation) of blood

Question 47

Give the normal adult score for peak flow

Answer 47

400-600 litres per minute

Question 48

Describe how a peak flow test is carried out

Answer 48

Record patients height and age Explain procedure and gain consent Set pointer on peak flow meter to zero Patient takes a deep breath and seal mouth round mouth piece Keep meter horizontal Breathe out as hard as possible Take reading Repeat Use the highest volume gained