Anatomy Of The Respiratory System

Question 1

Walls of the thoracic cavity

Answer 1

• anterior: sternum + costal cartilages
• lateral: ribs
• posterior: vertebral bodies
• inferior diaphragm

Question 2

What are the two analogies of the movement of the chest wall during breathing?

Answer 2

• bucket handle movement
• pump handle movement

Question 3

Explain the bucket handle movement of the chest wall

Answer 3

Ribs move out laterally to increase lung volume

Question 4

Explain the pump handle movement

Answer 4

Sternum moves anteriorly + ribs swing up like pump handle to increase lung volume

Question 5

What are the 3 types of intercostal muscles?

Answer 5

External
Internal
Innermost

Question 6

What intercostal muscles are used in inspiration?

Answer 6

External intercostal muscle

Question 7

What intercostal muscles are used in expiration (forced)?

Answer 7

Internal + innermost intercostal muscle

Question 8

What levels do these structure pass through the diaphragm?
- vena cava
- oesophagus
- aortic hiatus

How can you remember this?

Answer 8

• vena cava: T8
• oesophagus: T10
• aortic hiatus: T12

Number of letters in each

Question 9

Where should you insert a chest strain?
Why?

Answer 9

• Above the rib
• To avoid hitting the intercostal neurovascular bundles which lie beneath the ribs

Question 10

Outline venous drainage of the intercostal muscles

Answer 10

Intercostal vein > azygous vein > superior vena cava

Question 11

What nerve supplies the diaphragm ?

Answer 11

Phrenic nerve C3-5

‘C3,4,5 keeps the diaphragm alive’

Question 12

Outline the lobes of the lungs

Answer 12

3 right
2 left

Question 13

What do the oblique and horizontal fissure do?

Answer 13

Separate the lobes of the lungs

Question 14

What is the area in between the lungs called?

Answer 14

Mediastinum

Question 15

What spinal level splits the superior + inferior mediastinum?

Answer 15

C4-5

Question 16

Describe the layout of the hilum of the lungs

Answer 16

• airways: posterior
• branches of pulmonary arteries: superior
• tributaries of pulmonary veins: inferior

Question 17

What is the costodiaphragmatic recess?

Answer 17

The space where the lungs will expand in inspiration

Question 18

Outline the blood supply to the lungs

Answer 18

• pulmonary arteries directly from the heart
• bronchial artery directly from the aorta

Question 19

What blood supply helps the lungs during a pulmonary embolism when the pulmonary arteries are blocked?

Answer 19

Bronchial arteries

Question 20

Development of the respiratory tract

Answer 20

Develops as a diverticulum from the pharynx

Question 21

Role of the epiglottis

Answer 21

To ensure food and air enter oesophagus + trachea respectively

Question 22

What epithelial cells line the airways?

Answer 22

Ciliated pseudostratified columnar

Question 23

What makes up the lamina propria?

Answer 23

Basement membrane
Loose connective tissue

Question 24

Describe the layers of the airway walls

Answer 24

Mucosa
- epithelium: ciliated pseudostratified columnar + goblet cells
- lamina propria: basement membrane + loose connective tissue

Submucosa
- smooth muscle
- connective tissue: contain the bronchial mutinous glands

Cartilage in bronchi

Question 25

Layers of the mucosa in the airways

Answer 25

- **epithelium**: ciliated pseudostratified columnar + goblet cells - **lamina propria**: basement membrane + loose connective tissue

Question 26

Layers of the submucosa in the airways

Answer 26

Smooth muscle Connective tissue (contains the bronchial mucinous glands)

Question 27

What is also found in the walls of the bronchi but not the other airways?

Answer 27

Cartilage

Question 28

What is the carina?

Answer 28

The cartilage situated at the point where the trachea divides into the left and right main bronchus

Question 29

Function of type I pneumocytes

Answer 29

Squamous epithelial cells Responsible for gas exchange in alveoli

Question 30

Function of type II pneumocytes

Answer 30

Produce surfactant

Question 31

Nerve root of the phrenic nerve

Answer 31

C3-5 *‘C3,4,5 keeps the diaphragm alive*

Question 32

What makes up the neurovascular bundles below the ribs?

Answer 32

Intercostal vein Intercostal artery Intercostal nerve

Question 33

Where does the trachea start and end?

Answer 33

- **starts**: lower border of the cricoid cartilage C6 - **ends**: at T6 as it divides into the main bronchi

Question 34

Outline the attachment of the ribs

Answer 34

- 1-7 attach to sternum via costal cartilages - 8-10 attach to costal cartilage of 7th rib - 11-12 are floating ribs **TRUE RIB**: 7 letters > 1-7 true ribs **FLASE RIB**: 8 letters > 8-10 false ribs **FLOATING RIB**: 11 letters > 11-12 floating ribs

Question 35

Location of Clara cells

Answer 35

Terminal bronchioles

Question 36

Function of Clara cells

Answer 36

Produce surfactant + mucous

Question 37

Is air resistance in the bronchioles greater in expiration or inspiration?

Answer 37

**_expiration_** . - during **inspiration** the **alveolar expand** - this **increases radial traction** on the bronchioles - **bronchiole diameter is bigger** . - during **expiration**, **radial traction is lower** - so bronchioles have a **smaller diameter** - **increases air resistance**

Question 38

What effect does an absence of surfactant have?

Answer 38

- higher surface tension of alevoli - the pressure within the small alevoli is higher than large alevoli - small alveoli collapse in large alevoli - making fewer but larger air spaces

Question 39

How does surfactant reduce surface tension?

Answer 39

- surfactant is **amphipathic** - hydrophilic lie in the alveolar fluid - hydrophobic ends project into the alveolar gas - **surfactant molecles are interspersed between water molecules** - **bonds disrupted** between molecules - **surface tension reduces**

Question 40

How much of the tidal volume reaches the alevoli?

Answer 40

2/3rds

Question 41

Blood supply to the visceral pleura

Answer 41

Bronchial arteries

Question 42

Blood supply to the parietal pleura

Answer 42

Intercostal arteries

Question 43

What do the intercostal nerves innervate?

Answer 43

- **Sensory**: parietal pleura + kin overlying each intercostal space - **Motor**: intercostal muscles

Question 44

What does the oblique fissure separate?

Answer 44

- **Right**: middle and inferior lobes - **Left**: upper and lower lobes

Question 45

What does the horizontal fissure separate?

Answer 45

Right superior and middle lobes