Resp - Anatomy

Question 1

What are the zones of the respiratory tree?

Answer 1

(1) Conducting zone (2) Respiratory zone

Question 2

What do the large airways of the conducting zone include?

Answer 2

Large airways consist of nose, pharynx, larynx, trachea, and bronchi.

Question 3

What do the small airways of the conducting zone include?

Answer 3

Small airways consist of bronchioles and terminal bronchioles (large numbers in parallel –> least airway resistance).

Question 4

Which part of the respiratory tree has the least airway resistance, and why?

Answer 4

Small airways consist of bronchioles and terminal bronchioles (large numbers in parallel –> least airway resistance).

Question 5

What is versus is not the function of the conducting zone? As a result, what kind of space is it considered to be?

Answer 5

Warms, humidifies, and filters air but does not participate in gas exchange –> “anatomic dead space”

Question 6

What is the extent of cartilage in the conducting zone? What else extends this far?

Answer 6

Cartilage and goblet cells extend to end of bronchi

Question 7

What is the function of pseudostratified ciliated columnar cells? To where in the respiratory tree do they extend, and into what kind of cells do they transition?

Answer 7

Pseudostratified ciliated columnar cells (beat mucus up and out of lungs) extend to beginning of terminal bronchioles, then transition to cuboidal cells

Question 8

To where in the respiratory tree do airway smooth muscles extend?

Answer 8

Airway smooth muscles extend to end of terminal bronchioles (sparse beyond this point)

Question 9

What does the respiratory zone of the lung include?

Answer 9

Lung parenchyma; consists of respiratory bronchioles, alveolar ducts, and alveoli

Question 10

What is the function of the respiratory zone?

Answer 10

Participates in gas exchange

Question 11

What type of cells are in the respiratory bronchioles? What kind of cells do they become, and where?

Answer 11

Mostly cuboidal cells in respiratory bronchioles, then simple squamous cells up to alveoli.

Question 12

What is the function of alveolar macrophages, where, and why?

Answer 12

Respiratory zone - No cilia. Alveolar macrophages clear debris and participate in immune response

Question 13

Draw the inside and outside of alveoli, including and labeling the following: (1) Alveolar capillary beds (2) Alveoli (3) Alveolar duct (4) Alveolar sacs (5) Pulmonary artery (6) Pulmonary vein.

Answer 13

See p. 594 in First Aid 2014 for visual

Question 14

What are 3 types of pneumocytes?

Answer 14

(1) Type I cells (2) Type II cells (3) Club (Clara) cells

Question 15

What is the percentage of alveolar surfaces associated with Type I pneumocytes?

Answer 15

97% of alveolar surfaces

Question 16

What function(s) do Type I pneumocytes serve? What type of cells are they, and why is this important?

Answer 16

Line the alveoli. Squamous; thin for optimal gas diffusion.

Question 17

What major 2 functions do Type II pneumocytes serve? What are the important implications of each of these functions?

Answer 17

(1) Secrete pulmonary surfactant –> decreased alveolar surface tension & prevention of alveolar collapse (atelectasis). (2) Also serve as precursors to type I cells and other type II cells. Type II cells proliferate during lung damage.

Question 18

What kind of cells are Type II pneumocytes, and how do they appear?

Answer 18

Cuboidal and clustered

Question 19

Briefly describe the histology of Club (Clara) cells.

Answer 19

Nonciliated; low-columnar/cuboidal with secretory granules

Question 20

What is another name for Club cells? What 3 functions do they serve?

Answer 20

Club (Clara) cells; (1) Secrete component of surfactant (2) Degrade toxins (3) Act as reserve cells

Question 21

What is the equation for collapsing pressure of alveoli? Relate this to alveoli tendency to collapse, stating the applicable law.

Answer 21

Collapsing pressure (P) = 2(surface tension) / radius; Alveoli have increased tendency to collapse on expiration as radius decreases (law of Laplace).

Question 22

What makes up Pulmonary surfactant, and which of these components is most important?

Answer 22

Pulmonary surfactant is a complex mix of lecithins, the most important of which is dipalmitoylphosphatidylcholine

Question 23

When does surfactant synthesis begin, and when are mature levels reached?

Answer 23

Surfactant synthesis begins around week 26 of gestation but mature levels are not achieved until around week 35

Question 24

What ratio in amniotic fluid indicates fetal lung maturity?

Answer 24

Lecithin-to-sphingomyelin ratio > 2.0 in amniotic fluid indicates fetal lung maturity

Question 25

How many lobes does the right versus left lungs have, and what function does this serve?

Answer 25

Right lung has 3 lobes; Left has Less Lobes (2)

Question 26

Where is the Lingula, and what is it?

Answer 26

Left Lung - Lingula (homologue of right middle lobe)

Question 27

Which lung is the more common site for inhaled foreign body, and why?

Answer 27

Right lung is more common site for inhaled foreign body because the right main stem bronchus is wider and more vertical than the left

Question 28

Where does an aspirated peanut travel if the patient is upright?

Answer 28

Aspirate a peanut: While upright - lower portion of right inferior lobe

Question 29

Where does an aspirated peanut travel if the patient is supine?

Answer 29

Aspirate a peanut: While supine - superior portion of the right inferior lobe

Question 30

Instead of a middle lobe, what does the left lung have, and what purpose does this serve?

Answer 30

Instead of a middle lobe, the left lung has a space occupied by the heart.

Question 31

What is the relation of the pulmonary artery to the bronchus at each lung hilus?

Answer 31

The relation of the pulmonary artery to the bronchus at each lung hilus is described by “RALS” - Right Anterior; Left Superior.

Question 32

Draw anterior and posterior views of the lungs, including and labeling the following for each lung (if applicable): (1) Horizontal fissure (2) Middle lobe (3) Inferior lobe (4) Oblique fissure (5) Superior lobe.

Answer 32

See p. 595 in First Aid 2014 for visual at middle right

Question 33

Into what does the trachea branch?

Answer 33

Trachea –> Right bronchus & Left bronchus

Question 34

What structure perforates the diaphragm at T8?

Answer 34

At T8: IVC

Question 35

What 2 structures perforate the diaphragm at T10?

Answer 35

At T10: esophagus, vagus (Think: CN 10; 2 trunks)

Question 36

What 3 structures perforate the diaphragm at T12?

Answer 36

At T12: (1) aorta (red) (2) thoracic duct (white) (3) azygos vein (blue); Think: “at T-1-2 it’s the red, white, and blue”

Question 37

What 6 structures perforate the diaphragm, and at what levels?

Answer 37

AT T8: IVC; AT T10: esophagus, vagus; AT T12: aorta, thoracic duct, azygos vein; Think: “Number of letters = T level, T8: vena cava, T10: ‘oesophagus’, T12: aortic hiatus” AND/OR “I (IVC) ate (8) ten (10) eggs (esophagus) at (aorta) twelve (12)”

Question 38

What spinal nerves innervate the diaphragm? What is the name of the main nerve?

Answer 38

Diaphragm is innervated by C3, 4, and 5 (phrenic nerve); Think: “C3, 4, 5 keeps the diaphragm alive”

Question 39

What can cause pain from diaphragm irritation? What are 2 places to which such pain can be referred?

Answer 39

Pain from diaphragm irritation (e.g., air or blood in peritoneal cavity) can be referred to shoulder (C5) and the trapezius ridge (C3, 4)