Respiratory System

Question 1

What happens during inspiration in breathing?

Answer 1

Diaphragm contracts - moves down
Increased volume in the thoracic cavity —> pressure decreases
Intrapulmonary pressure is lower than the atmospheric pressure resulting in air moving into the lungs

Question 2

What happens during expiration in breathing?

Answer 2

Diaphragm relaxes and moves up
Decreased volume of thoracic cavity –> increased pressure
Intrapulmonary pressure is greater than the atmospheric pressure, air moves out of lungs

Question 3

What units are intrapulmonary/intrapleural pressures etc measured in?

Answer 3

CmH2O

Question 4

When is there a 0cmH2O intrapulmonary pressure?

Answer 4

At the end of exhalation when atmospheric pressure = intrapulmonary pressure

Question 5

How does the intrapleural pressure change? What is the intrapleural pressure compared to the intrapulmonary pressure?

Answer 5

It fluctuates with breathing

Is 4cmH2O less than intrapulmonary pressure (-4cmH2O)

Question 6

What is the purpose of the pressure difference between the intrapleural and intrapulmonary spaces?

Answer 6

The pressure difference across the alveolar wall keeps the stretched lungs adherent to the the chest wall

Question 7

What is a pneumothorax? What happens as a result?

Answer 7

Air in the pleural space

Pressure difference between intrapleural and intrapulmonary space disappears
Lung recoils and collapses

Question 8

What is the difference between an open and closed pneumothorax?

Answer 8

Open = opening in the chest wall - atmospheric air enters pleural space

Closed = chest wall is intact, rupturing of the lung/visceral pleura —> air into pleural space

Question 9

What is used to treat a pneumothorax? How does it work?

Answer 9

Chest drainage system

Prevents air retuning to pleural space, straw attached to a chest tube and placed under fluid
Air moves out of lungs and cant be drawn back up the straw

Question 10

What is the role of surfactant during inspiration?

Answer 10

When alveoli expand —> surfactant molecules move further apart

Question 11

What is the role of surfactant during expiration?

Answer 11

Surfactant molecules move together —> surface tension reduced

Question 12

What can surfactant deficiency result in?

Answer 12

Stiff lungs and difficulty breathing

Question 13

Why are the inferior aspects of the lungs curved upwards?

Answer 13

Sits on top of the domed diaphragm

Question 14

Why is the right lung often seen higher on x rays?

Answer 14

Due to the liver

Question 15

What is the lobe structure of the right and left lung?

Answer 15

Right = 3 lobes
Left = 2 lobes

Question 16

What happens in the conducting portions of the respiratory system?

Answer 16

Air is moved from one place to the next (no gas exchange)

Question 17

What happens at the respiratory portions of the respiratory system?

Answer 17

Gas exchange

Question 18

Where does the respiratory system contain mucous membranes?

Answer 18

Lining the conducting portion of the respiratory tract

Question 19

Where are serous membranes found in the respiratory system?

Answer 19

Lining the pleural sac of each lung

Question 20

What is the outer and inner layer of each pleural sac called? What lies between the two layers?

Answer 20

Outer = parietal serosa
Inner = visceral serosa
Lubricating fluid

Question 21

What is a pleural effusion?

Answer 21

When there is a watery transudate present in the pleural space

Question 22

How is fluid drained from the pleural cavity?

Answer 22

Using a wide bore needle through the 7th intercostal space under ultrasound guidance

Question 23

Why is it important to avoid; a) the inferior border of each rib and b) anywhere below the 7th intercostal space when draining fluid from the pleural space?

Answer 23

Blood vessels and nerves pass by the inferior border of each rib

Any lower than the 7th, may penetrate the diaphragm

Question 24

What does impingement of the right or left phrenic nerve result in?

Answer 24

Paralysis of the diaphragm

Question 25

What does impingement of the brachial plexus result in?

Answer 25

Wasting of the muscles in the lower arm

Question 26

What does impingement of the sympathetic trunk result in?

Answer 26

Droopy upper eyelid

Question 27

What does impingement on the left recurrent laryngeal nerve result in?

Answer 27

Hoarse voice

Question 28

What structures form the conducting portion of the respiratory tract?

Answer 28

``` Nasal cavity Pharynx Larynx Trachea Primary bronchi Secondary bronchi Bronchioles Terminal bronchioles ```

Question 29

What structures form the respiratory portion of the respiratory tract?

Answer 29

Respiratory bronchioles Alveolar ducts Alveoli

Question 30

Which structure of the respiratory system are found inside/outside the lungs?

Answer 30

Outside = nasal cavity to primary bronchi Inside = secondary bronchi to alveoli

Question 31

What epithelium is found from the nasal cavity all the way through to the bronchioles?

Answer 31

Pseudostratified ciliated epithelium with goblet cells

Question 32

Where is pseudostratified ciliated epithelium with goblet cells found in the respiratory system?

Answer 32

From the nasal cavity ---> bronchioles

Question 33

Which type of epithelium is found in the terminal bronchioles?

Answer 33

Simple columnar ciliated epithelium with clara cells

Question 34

What epithelium is found in the respiratory bronchioles and alveolar ducts?

Answer 34

Simple cuboidal epithelium with less cilia and with clara cells

Question 35

Which epithelium is found in the alveoli?

Answer 35

Simple squamous epithelium

Question 36

What are the 2 regions of the nasal cavity?

Answer 36

Olfactory regions | Non-olfactory regions

Question 37

Give a difference between the olfactory and non-olfactory regions?

Answer 37

Olfactory region contains olfactory cells and no goblet cells Non-olfactory region contains mucous glands

Question 38

What does the larynx consist of?

Answer 38

False vocal cord Ventricles True vocal cord

Question 39

What is the purpose of the true vocal cord of the larynx?

Answer 39

Prevents foreign objects from reaching the lungs - lined with stratified squamous epithelium

Question 40

What protects the lumen of the trachea?

Answer 40

C-shaped hyaline cartilage ring

Question 41

What is the position of the oesophagus compared to the trachea? What muscle is associated with the trachea?

Answer 41

Oesophagus behind the trachea Trachealis muscle

Question 42

What does the trachea divide into? Where in the body?

Answer 42

2 primary bronchi in the mid-thorax

Question 43

What are differences in histology between the trachea and primary bronchi?

Answer 43

Same histology - however the primary bronchi have complete hyaline cartilage rings and complete smooth muscle rings

Question 44

Which primary bronchus is more prone to lodging of foreign objects and why?

Answer 44

Right bronchus More vertical path

Question 45

What is the structure of the wall of the trachea (and largely the primary bronchi)?

Answer 45

Pseudostratified ciliated epithelium ---> lamina propria ---> submucosa with mucous glands ---> c shaped cartilage

Question 46

What happens in COPD with regards to cilia and mucus?

Answer 46

There is hypertrophy of mucousal glands and hyperplasia of goblet cells ---> more mucus And less cilia to move it

Question 47

What is the difference in structure between primary bronchi and secondary (and tertiary) bronchi?

Answer 47

Cartilage arranged as crescent shaped islands rather than full rings

Question 48

What is the typical size of a bronchiole?

Answer 48

1mm or less in diameter

Question 49

What is the structure of a bronchiole?

Answer 49

Has no cartilage or glands

Question 50

What keeps bronchioles open?

Answer 50

Alveoli due to their elasticity

Question 51

Which blood vessels supply the lungs with oxygenated blood?

Answer 51

Bronchial arteries

Question 52

What happens to bronchioles during asthma? How does this affect breathing?

Answer 52

Bronchoconstriction - walls no longer held open by alveoli More difficulty during expiration

Question 53

When do goblet cells give way to clara cells in the respiratory tract?

Answer 53

From terminal bronchioles onwards

Question 54

What two things do clara cells produce?

Answer 54

Secretes a surfactant lipoprotein - prevents walls sticking together Secretes clara cell protein (CC16) marker for lung damage

Question 55

What is the diameter of terminal bronchioles?

Answer 55

Less than 0.5mm

Question 56

Which parts of the respiratory tract open on to alveoli?

Answer 56

Respiratory bronchioles Alveolar duct Alveolar sac

Question 57

What is an alveolar sac?

Answer 57

Air space into which many alveoli open

Question 58

Alveolar walls are supported by a basketwork of...

Answer 58

Elastic and reticular fibres

Question 59

What two types of cells are found in the alveolar walls? In what percentages are they found?

Answer 59

Type 1 pneumocytes (90%) | Type 2 pneumocytes (10%)

Question 60

What is the function of type 1 pneumocytes?

Answer 60

For gas exchange

Question 61

What is the function of type 2 pneumocytes?

Answer 61

Production and release of surfactant

Question 62

What other types of cells are found lining the alveolar surface (excluding type 1/2 pneumocytes)?

Answer 62

Macrophages

Question 63

What is a hallmark sign of emphysema?

Answer 63

Pursed lip breathing

Question 64

What causes emphysema?

Answer 64

Destruction of alveolar walls ---> bronchioles collapse ---> difficult for lungs to empty

Question 65

What is pneumonia?

Answer 65

Inflammation of the lung caused by bacteria | Lung consolidates as the alveoli fill with inflammatory cells