(03) Respiratory System II

Question 1

(Bronchioles)

1. arise from what?
2. branch into several generations and end as what?
3. What differentiates them from bronchi?

Answer 1

1. bronchi
2. terminal bronchioles
3. walls lack cartilage

Question 2

(Bronchioles)

(Epithelium)

1. what is it like?
2. when do cilia start to disappear?

Answer 2

1. ciliated simple columnar/cuboidal
2. as terminal bronchioles become respiratory bronchioles

Question 3

(Bronchioles)

(Epithelium)

1-4. What are the four cell types?

Answer 3

1. goblet cells
2. ciliated cells
3. bronchiolar secretory cells
4. brush cells

Question 4

(Bronchioles)

(Epithelium)

(Goblet Cells)

1. numbers increase or decrease distally?
2. until entirely absent in what?

Answer 4

1. decrease
2. terminal bronchioles

Question 5

(Bronchioles)

(Epithelium)

(Ciliated Cells)

1. most numerous, increase or decrease caudally?

Answer 5

1. decrease

Question 6

(Bronchioles)

(Epithelium)

(Bronchiolar Secretory Cells - Clara cells)

1. increase or decrease distally along the length of the bronchiole
2. histologically they have dome shaped apices that do what?

(Function)

3. secretion of what that does what?
4. what else?

Answer 6

1. increase
2. protrude into lumen
3. surface-active protein lipoprotein that prevents luminal adhesion
4. metabolize and detoxify xenobiotics (xeno = foreign)

Question 7

(Bronchioles)

(Epithelium)

(Brush cells)

1. columnar cells that bear what?
2. Basal surface is in synaptic contact with what?

Answer 7

1. microvilli
2. afferent nerve endings (appear to play a sensory role)

Question 8

(Bronchioles)

(Lamina Propria)

1. consists of loose connective tissue with many lymphoccytes and elastic fibers?
2. are there cartilage or glands?

Answer 8

2. no

Question 9

(Bronchioles)

(Muscularis Mucosae)

1. Consists of smooth muscle that is how thick in the tertiary (terminal) bronchiole
2. What occurs in asthma?

(Tunica Mucosa)

3. comprised of loose connective tissue with many elastic fibers

Answer 9

1. one layer thick
2. constriction of smooth muscle

Question 10

(Bronchioles)

(Innervation)

1. parasympathetic does what?
2. and sympathetic?

Answer 10

1. constriction of smooth muscle
2. dilation

Question 11

(Bronchioles)

1. What extend further down the respiratory tree than glands?
2. This has functional significance in that it minimizes the possibility of what occuring?

Answer 11

1. cilia
2. secretions “leaking” into the exchange portion of the lung

Question 12

(Transitional Zone - between conducting and respiratory portion)

1. Respiratory bronchiole - plays what two roles? well developed in what? poorly developed in what?
2. similar to terminal bronchiole but what?
3. what cells predominate?

Answer 12

1. conducting and gas exchange; monkeys and carnivores; horse and man
2. alveoli interrupt less than half of the wall
3. ciliated cells and clara cells

Question 13

(Respiratory Zone - where most the gas exchange occurs)

(alveolar ducts)

1. similar to respiratory bronchiole but alveoli do what?

Answer 13

1. interrupt more than half of the wall

Question 14

(Respiratory Zone - where most the gas exchange occurs)

(Alveoli)

1. main functional units of the respiartory system where gas exchange occurs (~300 X 10^6 total, each 0.3 mm diameter)
2. Spherical structures lined by an alveolar epithelium composed of what two cell types?
3. What lies between two adjacent alveolli?

Answer 14

2. Type 1 and 2 pneumocytes
3. Interalveolar septum (wall) (contains capillaries, fibroblasts, elastic and reticular fibers and macrophages/lymphocytes)

Question 15

(Respiratory Zone - where most the gas exchange occurs)

1-5. What are the five cell types in the alveolar wall?

(Alveoli)

Answer 15

1. endothelial cell (30%) - continuous with fenestrated
2. Type I pneumocyte (8%) – squamous
3. Type II pneumocyte (16%)
4. fibroblasts and mast cells (36%)
5. macrophages (10%)

Question 16

(Alveoli)

(Type 1 Pneumocytes - Type 1 alveolar epithelial cells)

1. squamous cells
2. what between adjacent cells prevent fluid leakage into air space?
3. major or minor cell type in alveoli?
4. are they readily permeable to gases?

Answer 16

2. tight junctions
3. major (97% of alveolar surface)
4. yes

Question 17

(Alveoli)

(Type II pneumocytes or Great Alveolar Cells)

1. cuboidal cells interposed between the type I pneumocytes and bulging into alveolar lumen (3% of alveolar lining)
2. Characterized by the presence of what?
3. Produce what?
4. What is seen in animals born prematurely (neonatal respiratory distress syndrome)? leads to what?
5. is there a constant turnover of srfactant?

Answer 17

2. cytoplasmic lamellar bodies (continuously synthesized and released apically)
3. surfactant (dipalmitoyl phosphatidylcholine), an extracellular alveolar which lowers surface tension and prevents collapse of alveolus on expiration. (Alveoli can more easily remain open and are more stable)
4. lack of surfactant; stiffness of lungs and collapse of alveoli
5. yep

Question 18

(Alveoli)

(Alveolar macrophages - dust cells)

1. derived from what that migrate from what?
2. found where?
3. contain phagocytized inclusions such as dust and airborne particles
4. increase in failure of what?

Answer 18

1. monocytes that migrate from capillaries
2. alveolar walls and lumen
3. heart failure (commonly referred to as heart failure cells)

Question 19

(Alveoli)

(Gas Exchange Barrier)

1-3. what are the three layers?

Answer 19

1. alveolar epithelial cell
2. fused basement membranes of type 1 epithelium and endothelium
3. capillary endothelial cell

Question 20

(Alveoli)

1. alveoli communicate with adjacent alveoli through what?
2. what do these do?

(Note)

3. each blood cell spends how much time in capillary network of lung? traverses how many alveoli in that time? allowing what to occur?

Answer 20

1. alveolar pores (that are 3-15 um in diameter)
2. help equalize pressure between alveoli
3. 3/4 second; 2 or 3 alveoli; gas equilibration

Question 21

(Alveoli)

(Neuroendocrine Cells)

1. Small cells containing dense granules (EM) found in the epithelia from where to where?
2. part of what system?
3. appear to be involvend in paracrine, regulatory functions
4. visible in routine staining preparations?
5. occur singly or in small groups, some of these are innervated
6. give rise to what disease?

Answer 21

1. larynx to the bronchiolo-alveolar junction

2 APUD (Amine precursor uptake and decarboxylation) series of cells [a cell capable of amine precursor uptake and decarboxylation and of synthesizing and secreting polypeptide hormones]

4. no
5. bronchiol carcinoma (tumor of bronchi or bronchioles)

Question 22

Check out the graph in the book a bunch

Question 23

(Blood supply)

1. arterial consists of what two?
2. venous?

Answer 23

1. arterial and venous
2. all pulmonary veins

Question 24

(Blood supply)

(Arterial)

(pulmonary)

1. low or high pressure system?
2. more or fewer elastic or collagen fibers?
3. receives the entire what?

(bronchial)

4. supplies what?

Answer 24

1. low
2. fewer
3. entire right ventricular output
4. large bronchi, major pulmonary blood vessels and lymph nodes

Question 25

(Pulmonary lymphatics)

1. are throuhgout the interstitium - are they in the interalveolar space?

Answer 25

1. no

Question 26

(Innervation)

1. What innervate respiratory smooth musculature?
2. general viscearl afferents carried primarily in the vagus nerve originate from what?

Answer 26

1. general visceral efferent fibers from the vagus nerve and thoracic segments of the sympathetic trunk
2. mechanoreceptors in the lung and conductive passages