Anatomy of Lungs and Airways

Question 1

What are the functions of the respiratory system?

Answer 1

Gas Exchange, Acid Base balance, Protection from infection and Communication Via Speech

Question 2

What is Gas Exchange?

Answer 2

Oxygen added to the blood from the air, Carbon dioxide removed from the blood into the air.

Question 3

Why is Oxygen needed in the body?

Answer 3

To produce energy to fuel cells so they can carry out their functions.
To fuel aerobic respiration.
The brain to retain consciousness.

Question 4

Where is the only location of Gas exchange?

Answer 4

Alveoli

Question 5

What are the two types of Circulation?

Answer 5

Pulmonary Circulation and Systemic circulation

Question 6

What is systemic circulation?

Answer 6

Delivers oxygen to tissues and picks up carbon dioxide.

Question 7

What is pulmonary Circulation?

Answer 7

More localised. Blood from lungs to heart and heart to lungs. Delivers Carbon dioxide to lungs and picks up oxygen.

Question 8

What is an artery?

Answer 8

Carries blood away from the heart. Generally carries oxygenated blood to peripheral tissues.

Question 9

What is a vein?

Answer 9

Carry blood towards the heart. Generally deoxygenated.

Question 10

What does the Pulmonary Artery carry?

Answer 10

Deoxygenated away from the heart to the lungs.

Question 11

What is the Pulmonary Vein?

Answer 11

Oxygenated blood from the lungs to the heart.

Question 12

What is the relationship between the cardiovascular and respiratory systems.

Answer 12

Energy demand increased by working muscles - Rate and depth of breathing increases - Substrate O2 acquisition - waste disposal CO2 (TOXIC).
Heart rate & Force of contraction speeds up - substrate delivery to muscle via blood - waste removal via blood.

Question 13

What occurs at the systemic Capillaries?

Answer 13

O2 moves from blood to cells, CO2 moves from cells to blood.

Question 14

What are systemic Capillaries

Answer 14

Arteries that have branched. They have very thin walls. Only site of gas exchange.

Question 15

In the steady state, what is the net volume of oxygen exchanged in the lungs per unit time equal to?
And what does it prevent?

Answer 15

The net volume exchanged in the tissues.
Same applies for CO2.
Prevents the build up of gas in circulation.

Question 16

What are the average volumes of gas exchanged per minute?

Answer 16

250ml O2 consumed.

200ml CO2 produced

Question 17

What is the breathing rate at rest?

Answer 17

10-20 breaths/min

Question 18

What is the breathing rate at Maximum exercise?

Answer 18

40-45 breaths/min

Question 19

Describe the role of the nose?

Answer 19

Air enters. Cilia and mucus trap particles and warm and moisten the air. (Air must be in solution for gas exchange)

Question 20

What is the Pharynx also known as?

Answer 20

Throat

Question 21

Role of the Epiglottis?

Answer 21

Small flap of tissue folds over and stops food from entering it when you swallow

Question 22

Role of Larynx (vocal chords)?

Answer 22

Vibrate to produce sound

Question 23

Role of bronchus?

Answer 23

Air moves from trachea into right and left bronchi, which lead inside the lungs.

Question 24

What to Bronchi divide to produce?

Answer 24

Open ended sacks called Alveoli

Question 25

What makes up the Upper Respiratory Tract?

Answer 25

Nasal cavity, Pharynx, Larynx, Epiglottis

Question 26

What makes up the Lower Respiratory Tract?

Answer 26

Trachea, both lungs, Left and right bronchus, diaphragm. | Anything in the thoracic cavity

Question 27

How Many lobes is the right lung split into and what are they called?

Answer 27

3. The SUPERIOR lobe - separated by horizontal fissure to the - MIDDLE lobe - separated by oblique fissure to the - INFERIOR

Question 28

How many Lobes does the Left lung have?

Answer 28

2 (in most cases). | SUPERIOR and INFERIOR separated by oblique fissure.

Question 29

What covers the heart?

Answer 29

Fibrous layer of Pericardium

Question 30

What is the space that sites between the lungs and ribcage called? and its Function?

Answer 30

Pleural Cavity. | Fundamental in expanding the lungs. Normally held against the ribcage.

Question 31

What are the names of the divided trachea branches?

Answer 31

Trachea bifurcates to give primary bronchi that split into 3 secondary bronchi on the right side (lobes). Secondary bronchi split again to broncho pulmonary segments (unique tertiary bronchi or Bronchiole)

Question 32

How are the right and left primary bronchi arranged?

Answer 32

Right is more upright - almost vertical trajectory = common to find foreign bodies in this side.

Question 33

How is the patency of airways maintained?

Answer 33

Semi-rigid tubes held open by C-shaped rings of cartilage.

Question 34

Where does the c-shaped cartilage rings stop? what what hold them open?

Answer 34

Not found in Tertiary bronchi (Bronchiole), which are held by physical forces in thorax

Question 35

Where is the most resistance found in airways and why?

Answer 35

Most resistance in the upper airways as the diameter isn't increased proportionate with the amount of air passing through it. THINK about driving from country into city - Bottleneck

Question 36

What does contraction cause?

Answer 36

Decreased diameter or airway = increased resistance

Question 37

What does Relaxation cause?

Answer 37

Increased diameter = decreased resistance

Question 38

What changes the diameter of Bronchioles?

Answer 38

Smooth muscle

Question 39

Explain the structure of where gas exchange occurs?

Answer 39

Capillary beds found directly over Alveoli - both must have walls thin for gas exchange.

Question 40

What carries O2 from the Alveoli to the heart?

Answer 40

The pulmonary vein

Question 41

What is the role of elastic fibres?

Answer 41

Allow expansion and release elastic energy to push air out during expiration.

Question 42

Is expiration passive or active?

Answer 42

Passive. Energy has already been invested in the elastic fibres which is released.

Question 43

What are the 2 cell types found in Alveoli?

Answer 43

Type 1 cells - Gas exchange | Type 2 - specialist cells that produce Surfactant. Too thick for gas exchange.

Question 44

What is Anatomical dead space?

Answer 44

Area of no gas exchange as the walls are too thick.

Question 45

What is the function of mucus?

Answer 45

Moistens air, Traps particles, provides large surface area for cilia to act on, Goblet cells, Subepithelial glands.