Respiratory System

Question 1

Functions of the respiratory system

Answer 1

Gaseous exchange
Acid-base balance
Phonation
Pulmonary defence mechanism
Pulmonary metabolism

Question 2

Components of the respiratory system

Answer 2

-superior lobe
-middle lobe
-inferior lobe

Question 3

What are the functional zones in the airways

Answer 3

Conducting zone
Respiratory zone

Question 4

Outline the conducting zone

Answer 4

One place to another
First 16 generations
No alveolar exchange
Consists of trachea, bronchi, bronchioles

Question 5

Outline the respiratory zone

Answer 5

Respiratory element of active gaseous exchange
Alveoli present between generation 17-23
Gaseous exchange

Question 6

What are the muscles involved in respiration

Answer 6

Diaphragm
Intercostals
Accessory muscles

Question 7

Are respiratory muscles skeletal or smooth muscles

Answer 7

Skeletal

Question 8

Compare the diaphragm to intercostal muscles

Answer 8

Diaphragm is most powerful, intercostals are less powerful

Question 9

How is respiratory air flow determined

Answer 9

By the pressure difference between mouth and alveoli

Question 10

Define Pip

Answer 10

intrapleural pressure (intrathoratic pressure)

Question 11

Define Ptp

Answer 11

transpulmonary pressure

Question 12

Define Palv

Answer 12

Alveolar pressure

Question 13

Define Patm

Answer 13

Atmospheric pressure

Question 14

Name factors affecting breathing

Answer 14

Resistance
Compliance

Question 15

Outline resistance

Answer 15

Resistance of respiratory tract to airflow during inspiration & expiration
Affected by diameter of airways
-expiratory problem
-increasing respiratory rate

Children are at greater risk as they have:
Smaller airways
Higher resting respiratory rates

Question 16

Outline compliance

Answer 16

Measure of the lungs ability to stretch and expand (distensability of elastic tissue)

Expandability of lungs:
Low compliance-fibrosis
High compliance- emphysema
Value varies as lungs inflates

Question 17

Examples of obstructive diseases

Answer 17

Asthma
Bronchitis
COPD

Question 18

Outline Asthma: Type 1 hypersensitivity

Answer 18

Allergic or immediate hypersensitivity
Develop IgE antibodies in response to harmless antigens

Question 19

Outline the initial allergen encounter in asthma

Answer 19

Allergen inhaled, ingested or by contact
Adaptive immune response by B cells that form plasma cells to make IgE to allergen, IgE enters circulation and binds to mast cells in tissues

Question 20

Outline the subsequent allergen encounter

Answer 20

Allergen inhaled, injected or by contact
Cross-linkage causes mast cells to degranulate and release:
-vasoreactive amines (histamine)
-cytokines/chemokines
-leukotrienes

Question 21

What is a restrictive disease.

Answer 21

Anything that decreases compliance

Question 22

Outline Emphysema

Answer 22

Destruction of alveolar walls- large air spaces that are not cleared of air on exhalation (air trapping)

↓elastic fibres → ↓elastic recoil
Characteristic ‘barrel chest’
↓ gas exchange → ↓O2 diffusion → ↓O2 levels in blood

Consistent exposure to irritants- smoke,dust,chemical irritants

Question 23

Outline surfactant

Answer 23

Lipoprotein secreted by Type II alveolar cells
Part of the liquid film lining the alveoli
Lowers surface tension

Question 24

When surfactant lowers surface tension what does it cause

Answer 24

Increases compliance
Improves work of breathing

Question 25

What are the two principle causes of COPD
(Chronic Obstructive Pulmonary Disease)

Answer 25

Emphysema and Chronic Bronchitis