Structure of The Airway

Question 1

What structures form the conducting part of the respiratory tract? (6)

Answer 1

nasal cavity, pharynx, larynx, trachea, bronchi, bronchioles

Question 2

What structures form the respiratory part of the respiratory tract?

Answer 2

respiratory bronchioles, alveolar ducts, alveoli

Question 3

What are the structures of the nasal cavity? (5)

Answer 3

nose, septum, lateral walls with conchae, meats, airway

Question 4

Where is entry into the nasal cavity?

Answer 4

the nares

Question 5

What holds open the nasal cavity?

Answer 5

bone and cartilage

Question 6

Where is the nasal cavity found?

Answer 6

above the oral cavity, between the two orbits, posterior to the nose and anterior to the nasopharynx

Question 7

What is the nasal cavity lined with including the type of cells?

Answer 7

• highly vascularised mucosal membrane lined with respiratory epithelium
• pseudo stratifies ciliated columnar interspersed with goblet cells (secrete mucus)

Question 8

What is the nasal septum?

Answer 8

midline structure that separates right and left nasal cavities
made of septal cartilage (anterior part) and bone (posterior part)

Question 9

What are the nasal conchae (turbinate)?

Answer 9

curved shelves of bone found on the lateral wall of the nasal cavity
there are three - superior, middle, inferior
they provide turbulence and increase the surface area for air flow and heat exchange

Question 10

What are the nasal meatus/?

Answer 10

nasal passage of the nasal cavity under/lateral to each concha (superior, middle , inferior)

Question 11

What are the function of sinuses?

Answer 11

• lighten the skull
• produce mucus that moisturises the inside of the nose - assist in warming air - clearance of mucus is dependent on ciliary action

Question 12

What are the 4 main sinuses?

Answer 12

• frontal
• sphenoid
• ethmoid
• maxillary

Question 13

What are the three parts of the pharynx?

Answer 13

• nasal cavity (nasopharynx)
• oral cavity (oropharynx)
• larynx (laryngopharynx)

Question 14

What is the function of the nasal cavity (nasopharynx)?

Answer 14

transport air - warm, moisturise and filter before air reaches lungs

Question 15

What is the function of the oral cavity? (oropharynx)

Answer 15

transports air, food and fluid

- operated by epiglottis

Question 16

What is the function of the larynx?

Answer 16

• allows air to pass without letting food block the airway

- contains the vocal cords

Question 17

What is the structure of the larynx?

Answer 17

• members tube suspended between cartilages
• controlled by muscles
• diameter may be altered to allow the passage of air only - speech and raising into-abdominal pressure
• aryepiglottic fold forms the laryngeal inlet which is the protective sphincter

Question 18

Where is the trachea?

Answer 18

• anterior to oesophagus
• medial to carotid arteries and internal jugular veins
• inferior to larynx
• thyroid glands surround upper portion

Question 19

Describe the structure of the trachea?

Answer 19

c-shaped rings of cartilage supporting a fibro-elastic and muscular air-transport tube
- tracheal muscle (posteriorly positioned) can alter the tracheal diameter

Question 20

What is the function of the trachea?

Answer 20

connects the larynx to the bronchi - for airflow

Question 21

What is the position of the trachea?

Answer 21

palpable anteriorly above suprasternal notch

- starts at C6 and ends at T4/5

Question 22

Explain the bronchi?

Answer 22

• each lung has one main bronchus (even though right lung has 3 lobes and left lung has 2)
• left lung has two lobar (secondary) bronchi - left superior lobar bronchus and left inferior lobar bronchus
• right lung has three lobar bronchi - right superior, right middle, right lower
• each lobar bronchi then divides into segmental bronchi

Question 23

How do bronchi divide into bronchioles?

Answer 23

bronchi > conducting bronchioles > terminal bronchioles > respiratory bronchioles > aveoli

Question 24

What supplies the bronchi with oxygenated blood?

Answer 24

bronchial arteries

Question 25

What epithelium is present in the trachea?

Answer 25

pseudostratified ciliated columnar with goblet cells

Question 26

What epithelium is present in the bronchi?

Answer 26

pseudostratified ciliated columnar - but cells are more flattened than in trachea

Question 27

What epithelium is present in the bronchiole?

Answer 27

ciliated columnar - flatter than bronchi

Question 28

What epithelium is present in the terminal and respiratory bronchioles?

Answer 28

non-ciliated cuboidal - thinner than in bronchioles - no goblet cells

Question 29

What allows the alveoli to be good at gas exchange?

Answer 29

- thin membrane containing capillaries | - high surface area

Question 30

What are the pleura?

Answer 30

a pair of membranes which line the thorax (cavity walls) and lungs - one continuous membrane

Question 31

What is the pleural cavity?

Answer 31

space between the layers of pleura | - it contains fluid to libricate the pleural surfaces allowing for smooth, gliding movements during breathing

Question 32

What is the visceral/pulmonary pleura?

Answer 32

pleura covering the lungs

Question 33

What contributes to easy inflation of the lungs?

Answer 33

- slightly negative pressure in the pleural cavity | - lung is highly elastic - and partially inflated - so like a balloon less energy is required to inflate

Question 34

What are the parietal pleura? name them

Answer 34

membranes which cover the cavity walls - depending on where the pleura is located a different name is used - cervical, costal, mediastinal, diaphragmatic

Question 35

Where does the cervical pleura lie?

Answer 35

?

Question 36

Where does the costal pleura lie?

Answer 36

?

Question 37

Where does the mediastinal pleura lie?

Answer 37

?

Question 38

Where does the diaphragmatic pleura lie?

Answer 38

?

Question 39

What happens if air gets into the parietal layer?

Answer 39

lung collapses due to loss of negative pressure - pneumothorax - air removed by inserting needle

Question 40

What separates the two lungs?

Answer 40

mediastinum

Question 41

Describe the structure of the left lung?

Answer 41

- slightly longer and narrower than the right lung - two lobes - superior and inferior - cardiac notch - lingula - oblique fissure - apex and base - hilum

Question 42

What is the hilum?

Answer 42

"root of the lung" | - structures pass into and out of the lung - main bronchus, pulmonary artery, pulmonary veins)

Question 43

What do the pulmonary arteries carry?

Answer 43

deoxygenated blood from the heart to lungs

Question 44

What do the pulmonary veins carry?

Answer 44

oxygenated blood from the lungs to heart

Question 45

Explain lung lymph drainage?

Answer 45

via a sub-pleural plexus and | plexus alongside the bronchi to the hilarity nodes

Question 46

Describe the structure of the right lung?

Answer 46

- slightly wider but shorter than left - due to right dome of diaphragm being higher on this side - 3 lobes - superior, middle, inferior - horizontal/transverse fissure and oblique fissure (lower one) - apex and base - hilum

Question 47

Describe the surface anatomy of the lungs?

Answer 47

- apex of lung and pleura are above the clavicle - the pleura extend down to the costal margin - but lungs end 2 rib spaces higher - during normal/quite respiration lungs do not extend to the lower parts of the pleural cavity

Question 48

Explain the mechanisms of respiration?

Answer 48

- inhalation must increase the diameters of the thorax to create a negative pressure - which sucks air into the lungs via the trachea and larynx - diaphragmatic contraction causes its descent - increasing its vertical diameter - rib elevation (uses intercostal muscles too) pushes the sternum up and forward, and the ribs outward to increase anteroposterior and lateral diameters - exhalation is by muscle relaxation and elastic recoil - passive

Question 49

What is the function of intercostal muscles?

Answer 49

expand the size of the thoracic cavity during respiration - raise the ribs and push sternum upwards

Question 50

What do the internal intercostals do?

Answer 50

depress the ribs pulling them inferiority as in deep exhalation

Question 51

What so the external intercostals do?

Answer 51

elevate and lift ribs in deep inhalation

Question 52

Explain the structure of the diaphragm?

Answer 52

- muscular at periphery - tendinous centrally - left and right domes - motor ans sensory suppled by the phrenic nerve (C3,4,5 keep it alive)

Question 53

Explain the function of the diaphragm?

Answer 53

during inspiration the domes of the diaphragm descend causing negative intrathoracic pressure but raising ire-abdominal pressure