Introduction and anatomy of lungs, airways and blood supply

Question 1

What is ventilation?

Answer 1

the movement of air into and out of the lungs, it does not include the exchange of gas with the blood.

Question 2

what are the main functions of the respiratory system?

Answer 2

• gas exchange
• acid-base balance- regulation of the extracellular fluid pH
• protection from infection
• communication via speech

Question 3

what is the function of gas exchange?

Answer 3

for transporting oxygen to cells so they can respire aerobically and removal of toxic carbon dioxide

Question 4

what is external respiration?

Answer 4

how we move oxygen from the environment to our cells and carbon dioxide away from our cells

Question 5

what sort of blood does the pulmonary artery carry?

Answer 5

oxygen poor, carbon dioxide rich

Question 6

what sort of blood does the pulmonary vein carry?

Answer 6

oxygen rich, carbon dioxide poor

Question 7

why does respiratory rate and depth of breathing increase when muscles are working during exercise?

Answer 7

to cater for the increased energy deman

it allows substrate (oxygen) acquisition and waste disposal (carbon dioxide) to speed up.

Question 8

why does heart rate and force of contraction increase when muscles are working during exercise?

Answer 8

to speed up substrate delivery to muscle via blood

and to speed up waste removal via blood

Question 9

where is the only point of gas exchange in the lungs?

Answer 9

the alveoli (gas is exchanged with capillaries)

Question 10

what is the steady state, in terms of gases?

Answer 10

there is a balance between net volume of oxygen/carbon dioxide exchanged at the lungs per minute and the net volume exchanged in the tissues.

Question 11

what is the role of the nose in the respiratory system?

Answer 11

air enters the body through the nose, cilia and mucus trap particles and air is warmed and moistened.

Question 12

what is the pharynx?

Answer 12

(aka throat) it is the section of the respiratory tract which is shared with the digestive system

Question 13

what is the epiglottis and what is its role in the respiratory system?

Answer 13

a small flap of tissue that folds over the trachea and prevents food from entering it when you swallow. it is horizontal when you swallow but vertical when breathing

Question 14

what is the larynx?

Answer 14

(aka voice box) contains vocal cords which vibrate to produce sound

Question 15

what is the trachea?

Answer 15

the section of the respiratory tract just below the larynx, it is made up of rings of cartilage that support and protect it

Question 16

what is a bronchus?

Answer 16

the bifurcates into two of these tubes which are the structures through which air enters and exits the lungs

Question 17

what is the upper respiratory tract?

Answer 17

it consists of everything in the respiratory tract from the larynx up

Question 18

what is the lower respiratory tract?

Answer 18

everything in the respiratory tract below the larynx

Question 19

why do we breath through our nose at rest?

Answer 19

• the nasal tract contains more crevices so hasd a larger surface are and so it is better at moistening air
• also better and warming air, this helps easily maintain body temp and requires less energy than breathing through the mouth

Question 20

how many lobes does the right lung have?

Answer 20

3

Question 21

how many lobes does the left lung have?

Answer 21

2

Question 22

how many secondary bronchi does the left lung have?

Answer 22

2

Question 23

how many secondary bronchi does the right lug have?

Answer 23

3

Question 24

where do tertiary bronchi take air to?

Answer 24

segments of the lung

Question 25

what is patency?

Answer 25

the condition of being open

Question 26

why are the cartilage rings in the trachea and bronchi important?

Answer 26

they maintain patency

Question 27

how does resistance change moving further into the lungs?

Answer 27

it decreases, this is because the total area of the airways increases

Question 28

what the conducting zone?

Answer 28

the trachea, bronchi and bromchioles

Question 29

what is the respiratory zone?

Answer 29

respiratory bronchioles, alveoli and alveolar ducts

Question 30

what is the function of the elastic fibres of the alveoli?

Answer 30

allows increase in volume of alveoli during inspiration and store energy which is released on expiration

Question 31

what is the function of type I alveolar cells?

Answer 31

gas exchange

Question 32

what is the function of the type II alveolar cells?

Answer 32

produce surfactant
reduces surface tension at alveolar surface
reduces work of breathing

Question 33

what is anatomical dead space?

Answer 33

the air inside the conduction zone of the respiratory tract

Question 34

what tissue is the lining of the upper respiratory tract?

Answer 34

ciliated pseudostratified columnar epithelium with gland (goblet cells), blood vessels and lymph nodes

Question 35

what happens to the lining of the respiratory tract moving from the nose to the alveoli?

Answer 35

epithelium becomes more squamous
cilia lost
mucous cells lost

Question 36

purpose of mucous?

Answer 36

traps particles
moistens air
provides large surface area for cilia to act on