Introduction and anatomy of lungs, airways and blood supply

Question 1

4 Functions of respiratory system

Answer 1

• protect from infection: lymphoid tissue
• Communication
• Gas exchange; Oxygen added and carbon dioxide removed
• Acid base balance; ECF pH= 7.4

Question 2

What does the respiratory system do to oxygen and carbon dioxide?

Answer 2

Acquires oxygen and removes carbon dioxide

Question 3

What does the cardiovascular system do to oxygen and carbon dioxide?

Answer 3

Transport oxygen to tissues and transport carbon dioxide away from cells

Question 4

What is External respiration?

Answer 4

Integration of respiratory and cardiovascular systems to facilitate the movement of gas from air to body cells

Question 5

Pulmonary circulation - blood carried in artery and vein

Answer 5

Artery carries deoxygenated blood (CO2 rich) and the vein is highly oxygenated

Question 6

Systemic circulation - blood carried

Answer 6

Arterial = oxygen rich venous = CO2 rich

Question 7

Pulmonary circulation - movement of blood

Answer 7

Between heart and lungs only

Oxygen from lung to blood and carbon dioxide from blood to lungs

Question 8

Systemic circulation - movement of blood

Answer 8

Everywhere else in the body and moves oxygen to the cells and carbon dioxide into the blood

Question 9

Steady state

Answer 9

Net volume of oxygen exchanged in lungs per unit time is equal to the net volume exchanged in tissues
Same for carbon dioxide

Question 10

What does the steady state prevent?

Answer 10

Gas build up - excess carbon dioxide leading to “swelling up”

Question 11

Average volumes of oxygen and carbon dioxide per breath

Answer 11

250ml oxygen and 200ml carbon dioxide

Question 12

What is the average and maximum breaths per minute?

Answer 12

10-20 and 40-45

Question 13

Respiratory system - components

Answer 13

pseudostratified ciliated columnar epithelia
glands 
vessels
lymph nodes 
mucous

Question 14

Upper respiratory tract (4)

Answer 14

• nose
• pharynx
• epiglottis
• larynx

Question 15

Lower respiratory tract (3)

Answer 15

• trachea
• bronchus
• lungs

Question 16

Nose

Answer 16

Cilia and mucous trap particles

warm and moisten air

Question 17

Epiglottis

Answer 17

Small flap of skin which is usually open but closes to prevent food going down the trachea

Question 18

Pharynx

Answer 18

Throat - shared with the digestive system

Question 19

Trachea

Answer 19

Stiff rings of cartilage keep this open

Question 20

Larynx

Answer 20

Voice box - where the respiratory and digestive systems separate

Question 21

Bronchus - how many secondary in each lung?

Answer 21

3 in right and 2 in left

Question 22

Lung

Answer 22

Contains blind ended sacs called alveoli

Question 23

Right lung lobes and dividers

Answer 23

superior lobe 
horizontal fissure
middle lobe 
oblique fissure 
inferior lobe

Question 24

Left lung lobes and divider

Answer 24

superior lobe
oblique fissure
inferior lobe

Question 25

Are pathogens more likely to stick in the left or right bronchus? Why?

Answer 25

Right | Right bronchus is closer to vertical and is wider

Question 26

Patent

Answer 26

Open airway which is unobstructed

Question 27

How are the larynx, trachea and bronchus kept open?

Answer 27

Rings of cartilage

Question 28

How are the bronchioles kept open?

Answer 28

Physical forces in the thorax

Question 29

What happens to the resistance going down the respiratory tract as it branches?

Answer 29

Resistance decreases as there is a larger number of the structures whereas near the start, trachea for example, although it is wider there is only 1 so the relative resistance is higher

Question 30

Contraction decreases diameter and does what to resistance?

Answer 30

Increases

Question 31

Relaxation increases diameter and does what to resistance?

Answer 31

Decreases

Question 32

What surrounds the alveoli to stretch when inspiring?

Answer 32

Elastic fibres

Question 33

Type 1 alveoli cells

Answer 33

Gas exchange - very thin

Question 34

Type 2 alveoli cells

Answer 34

Produce surfactant for ease of breathing

Question 35

Are capillaries in contact with type 1 or 2 alveoli cells?

Answer 35

Type 1

Question 36

Anatomical dead space

Answer 36

Air in the upper respiratory tract as the walls do not allow for gas exchange

Question 37

What are pneumocytes another name for?

Answer 37

Alveolar cells

Question 38

Going down the respiratory tract are goblet cells or cilia lost first?

Answer 38

Goblet cells

Question 39

Mucous

Answer 39

Moistens air and traps particles produced from goblet cells