Structure of lungs

Question 1

Describe the cartilage that forms the trachea

Answer 1

C- shaped rings of hyaline cartilage

Question 2

at what intervertebral discs does the trachea start and end?

Answer 2

C6 and T4/5

Question 3

Which muscle alters the tracheal diameter?

Answer 3

trachealis muscle

Question 4

Which lung are foreign bodies more likely to enter and why?

Answer 4

Right- due to the shape and size of the right bronchus (slightly more vertical, shorte and wider)

Question 5

how many lobes do each of the lungs have?

Answer 5

left= 2, right=3

Question 6

which arteries supply the bronchi with oxygenated blood?

Answer 6

bronchial arteries

Question 7

how many (secondary) lobar brochi do each of the lungs have and name them

Answer 7

Left=2, left superior lobar bronchus and left inferior lobar bronchus
right=3, right superior lobar bronchus, right middle lobar bronchus and right inferior lobar bronchus.

Question 8

what do the lobar bronchi divide into?

Answer 8

segmental bronchi

Question 9

what do segmental bronchi divide into?

Answer 9

smaller and smaller branches eventually becoming conducting bronchioles, then terminal bronchioles and then respiratory bronchioles.

Question 10

what do the respiratory bronchioles end in?

Answer 10

alveoli

Question 11

Cells that form the epithelium of the trachea

Answer 11

pseudo-stratifies, ciliated, columnar epithelium, interspersed with goblet cells

Question 12

how is the epithelium of the bronchi different to the trachea?

Answer 12

the height of cells is decreased (more flattened)

Question 13

Volume of mucus produced each day?

Answer 13

1 litre

Question 14

what are the c shaped cartilage rings replaced by as the bronchi branch into the lungs?

Answer 14

cartilage plates

Question 15

Describe epithelium in bronchioles (not terminal or respiratory)

Answer 15

ciliated columnar (flatter columnar to those in bronchi)

Question 16

is there muscle in the bronchioles?

Answer 16

yes there is a band of smooth muscle.

Question 17

Are there cartilage and glands in the bronchioles?

Answer 17

no, instead the bronchiole is held open by surrounding lung tissue

Question 18

what happens in the bronchiole during asthma?

Answer 18

the smooth muscle in the wall contracts which may excessively narrow the lumen. the lining of the airway also become swollen and inflamed, there may also be an increase in secretions.

Question 19

Describe epithelium in terminal and respiratory bronchioles

Answer 19

non-ciliated cuboidal (even flatter) and not interspersed with goblet cells

Question 20

Where does gas exchange occur?

Answer 20

alveoli

Question 21

what separates one alveoli from the next?

Answer 21

septae

Question 22

describe septae

Answer 22

alveolar walls are thin membranes containing capillaries

Question 23

What is the air-blood barrier for gas exchange?

Answer 23

the septae

Question 24

what do you call the space between the layers of pleura?

Answer 24

pleural cavity

Question 25

whats in the pleural cavity? why is this needed?

Answer 25

lubricating fluid allows smooth gliding movements between the 2 pleura

Question 26

What are the pleura?

Answer 26

The membranes which line the lungs and the cavity walls

Question 27

name the 2 pleura

Answer 27

parietal pleura and visceral/pulmonary pleura

Question 28

describe the parietal pleura and how it is named

Answer 28

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

Question 29

what do you call the pleura that covers the lungs?

Answer 29

visceral

Question 30

Are the parietal pleura and visceral pleura continuous with each other?

Answer 30

yes

Question 31

what separated the 2 lungs?

Answer 31

mediastinum

Question 32

in what ways are the 2 lungs different?

Answer 32

``` right= 3 lobes, left = 2 lobes left = longer and narrower ```

Question 33

why is the left lung longer and narrower than the right?

Answer 33

makes room for heart and pericardium

Question 34

describe the hilum

Answer 34

the 'root of the lung', whereby the main brochus, pulmonary artery and pulmonary veins pass into and out of the lung

Question 35

what brings deoxygenated blood to the lungs?

Answer 35

pulmonary artery

Question 36

what carried oxygenated blood away from the lungs?

Answer 36

pulmonary vein

Question 37

via what is the lung lymph drainage?

Answer 37

the sub-pleural plexus and a plexus alongside the bronchi to hilar lymph nodes

Question 38

why is the right lung shorter than the left?

Answer 38

the right dome of the diaphragm is higher on the right than on the left

Question 39

which structures are above the clavicle?

Answer 39

the apex of the lungs and apex of the pleura

Question 40

how many rib spaces higher do the lungs end before the pleura?

Answer 40

2

Question 41

what do the external intercostal muscles do and when?

Answer 41

When the external intercostal muscles contract during inhalation , the bring the ribs (and sternum)outwards and upwards

Question 42

what do the internal intercostal muscle do?

Answer 42

they contract and depress the ribs (pulling them further inwards and downwards) during deep expiration

Question 43

describe the structure of the diaphragm in regards to muscle and tendon

Answer 43

muscular at its periphery but tendinous centrally

Question 44

which nerve is in charge of motor and sensory supply?

Answer 44

``` phrenic nerve (c3,4,5) (c3,4 and 5 keep the diaphragm alive) ```

Question 45

during expiration describe the change in intrathoracic and intra-abdominal pressure

Answer 45

the intrathoracic pressure decreases (become negative), the intraabdominal presure increases

Question 46

what is pneumothorax?

Answer 46

When air enters the pleural cavity. Results in a collapsed lung.

Question 47

how do you treat pneumothorax (collapsed lung)?

Answer 47

a needle is inserted just above the rib to avoid damage to the neurovascular bundle that runs just inferior to each rib to remove the air from the pleural cavity to allow the lung to expand again

Question 48

what runs just inferior to each rib?

Answer 48

a neurovascular bundle