Respiratory System

Question 1

What does the trachea split into?

Answer 1

Right and left primary bronchus

Question 2

What is the top of the lung called?

Answer 2

Apex

Question 3

What counts as the upper respiratory tract?

Answer 3

• nasal cavity
• pharynx
• nasopharynx
• oropharynx
• laryngopharynx
• larynx

Question 4

What counts as the Lower respiratory tract?

Answer 4

• trachea
• bronchi
• bronchioles
• alveolar sacs
• alveoli

Question 5

What is the purpose of nasal cavities?

Answer 5

To warms and filter the air

Question 6

What does the pharynx connect?

Answer 6

The nasal and oral cavities to larynx and oesophagus

Question 7

What prevents choking as oesophagus and trachea is right next to each other?

Answer 7

Epiglottis
- stays up when breathing, exposing trachea
- down when eating, covering trachea

Question 8

What allows the trachea to remain open and withstand pressure changes?

Answer 8

Trachea is lined with C-shaped rings of cartilage

Question 9

What occupies the mediastinum?

Answer 9

Heart

Question 10

What is the pleura?

Answer 10

Closed sac of serous membrane containing serous fluid

Question 11

The position of the pleura?

Answer 11

Encloses the lungs

Question 12

Pleura function:

Answer 12

Lubricates the lungs and allows them to expand and deflate without friction

Question 13

What does the pleura cavity contain?

Answer 13

Surfactants

Question 14

How many divisions are in the lower respiratory tract?

Answer 14

2
- conducting zone
- respiratory zone

Question 15

What is the air like in the conducting zone?

Answer 15

Anatomical dead space
From nostrils to start of bronchioles
No alveoli

Question 16

What are type I alveoli cells?

Answer 16

Squamous
90% surface area and allows gas exchange with capillaries

Question 17

What are type II alveoli cells?

Answer 17

Cuboidal
10% of surface area and produces surfactant

Question 18

What lines the alveolar surface?

Answer 18

Macrophages for phagocytosis

Question 19

What protects the lung from infection?

Answer 19

Respiratory tract has an epithelial lining with cilia (synchronous wafting that causes coughing as it pushes the dust up) and goblet cells ( mucus secreting cells that traps dust and unwanted particles)

Question 20

Inspiration?

Answer 20

• EIM contract, pushing the rib cage up and out
• diaphragm flattens
• thoracic cavity increases so pressure is lower than atmospheric

Question 21

Expiration?

Answer 21

• EIC relaxes and diaphragm returns to domed shape
• pressure inside the lungs is higher as thoracic cavity is smaller
• air is expelled

Question 22

What is lung elasticity?

Answer 22

• amount of stretch in the lung
• it’s ability to return back to its original shape

Question 23

What is lung complicity?

Answer 23

• how easy it is for the lungs to stretch in the first place

Question 24

What is airway resistance?

Answer 24

How easy it is for air to move through the airway

Question 25

What is the role of the surfactant?

Answer 25

Reduces friction within alveoli and allows for easier expansion

Question 26

Peak expiration flow

Answer 26

Maximum speed of air flow during forced expiration

Question 27

Oxygen diffusion pathway

Answer 27

Alveolar fluid than membrane and basement membrane Interstium Capillary basement membrane Endothelial membrane Plasma RBC membrane

Question 28

How oxygen dissolves

Answer 28

O2 enters plasma and dissolves O2 enters RBC and binds to Hb Most of O2 is delivered to tissues by Hb Rest (2%) dissolved in plasma

Question 29

Why is there an increased need for O2 during pregnancy?

Answer 29

- mother, fetus and placenta require O2 - increased demand for gaseous exchange -accommodation for new gas exchange system (placenta)

Question 30

What happens to the nasopharynx during pregnancy?

Answer 30

- increased blood flow cause oedema - increased mucus due to increased oestrogen

Question 31

How does progesterone increase air flow?

Answer 31

Relaxes smooth muscle of bronchioles, reducing airway resistance

Question 32

Anatomical changes to the thorax during pregnancy:

Answer 32

- diaphragm raises by 4cm to make room for growing uterus - thorax cartilage relaxes so transverse diameter increases -subcostal angle increases so lungs have more space

Question 33

Closed glottis pushing (vasalva)

Answer 33

- breath holding during the duration of contraction -pressure induced by descent of diaphragm encourages descent of fetus -compresses fundus

Question 34

Open-glottis pushing (valsalva)

Answer 34

- slow expiration through pursed lips - transverse and oblique muscles contract -compresses the sides of the uterus encouraging fetal descent

Question 35

Where are peripheral chemoreceptors found and what do they measure?

Answer 35

Aortic arch Measures o2 and co2 conc in blood Relays information back to respiratory centre

Question 36

Where are central chemoreceptors found what their function?

Answer 36

- under the surface of the medulla - detect high levels of co2 -sends messages to respiratory centre to increase respiration rate

Question 37

How does progesterone affect the central chemoreceptors during pregnancy?

Answer 37

- increases sensitivity to concentration of co2 - stimulates over breathing

Question 38

What causes respiratory alkalosis?

Answer 38

Increased progesterone Allows for co2 diffusion from placenta into maternal bloodstream

Question 39

What happens tidal volume during pregnancy?

Answer 39

Increases by approximately 40% /200 ml in the first trimester

Question 40

What happens to pulmonary ventilation ( total air taken in 1 min) during pregnancy?

Answer 40

Increases by 40%

Question 41

What happens to residual volume (air left after max expiration) during pregnancy?

Answer 41

-decreases

Question 42

What happens to lung vital capacity during pregnancy?

Answer 42

Increases by 100-200ml

Question 43

What happens to the respiratory system following birth?

Answer 43

- intra abdominal pressure reduces Co2 concentration rise - ventilation return to pre-pregnancy state within 1-3 weeks