Introduction and Histology of Respiratory Tract Flashcards Preview

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Flashcards in Introduction and Histology of Respiratory Tract Deck (211):
1

What does the respiratory system work to do? 

Ensure that all tissues receive the oxygen that they need, and can dispose of the CO2 they produce 

2

What does blood do? 

In relation to gas exchange

Carries gases to and from tissues, where the lungs exchange them with the atmosphere 

3

What is the Kinetic Theory of Gases? 

Gases are a collection of molecules moving around a space, generating pressure by colliding with the walls of the space. As collisions become more frequent, and harder, the pressure goes up. 

4

What is Boyle's Law? 

If a given amount of gas is compressed into a smaller volume, the molecules will hit the wall more often, therefore pressure will rise. 

If temperature is constant, pressure is inversely proportional to volume

5

What is Charles' Law? 

The kinetic energy of molecules increases with temperature. As temperature increases, the molecules hit the walls more often, so pressure increases. 

Pressure is proportional to absoloute temperature (scale starts at absoloute zero) 

6

What is the Universal Gas Law? 

Pressure x Volume = Gas constant x Temperature (oK)

7

What does the Universal Gas Law allow? 

The calculation of how volume will change as pressure and temperature changes 

8

What is meant by partial pressure? 

In a mixture of gases, molecules of each type behave independently, so each gas exerts its own pressure, which is a portion of the total pressure- a partial pressure 

9

What is partial pressure calculated as? 

The same fraction of the total pressure as the volume fraction of the gas in the mixture 

10

What is meant by vapour pressure? 

In biological systems, gas mixtures are always in contact with water, so gas molecules dissolve, and water molecules evaporate, and then exert their own partial pressure- this is known as vapour pressure 

11

What is meant by saturated vapour pressure? 

When the rate of molecules entering and leaving water at the same time is equal, this is the saturated volume pressure 

12

How much water vapour  is in gases when they enter our body? 

In terms of saturation 

They are completely saturated with water vapour 

 

13

Why are gases entering our body completely saturated with water vapour? 

So they don't dry out our lungs

14

What does gas tension in liquids indicate? 

How readily a gas will leave the liquid, not (at least directly) how much gas is in the liquid 

15

What is tension equal to at equilibrium? 

Partial pressure 

16

How quickly is tension equilibrium reaching in the body? 

Very quickly 

17

What is the amount of gas that enters a liquid to establish a particular tension determined by? 

Solubility 

 

18

How is content of gas in a liquid calculated? 

Content = solubility x tension 

i.e. how easily a gas will dissolve x how readily it will leave 

19

What must happen if the gas reacts with a component of the liquid? 

With regards to tension and content 

The reaction must be complete before tension, and therefore content can be established 

20

What is total content equal to? 

Total content = Reacted gas + Dissolved gas 

21

What is meant by tidal volume? 

The lung volume that represents the amount of air that is displaced between normal inspiration an expiration, when extra effort is not required 

22

Draw a diagram illustrating-

  • Inspiratory capacity 
  • Expiratory reserve volume 
  • Residual volume 
  • Vital capacity 
  • Inspiratory reserve volume 
  • Tidal volume
  • Funtional residual capacity 
  • Total lung capacity 

A image thumb
23

What is meant by respiratory rate/pulmonary ventilation rate? 

The number of breaths taken in a set time, usually 60 seconds 

24

What are the two circulations of the lungs? 

  • Pulmonary
  • Bronchial 

 

25

What is the bronchial circulation part of? 

The systemic circulation 

26

What is the purpose of the bronchial circulation? 

It meets the metabolic requirements of the lungs

27

What is the pulmonary circulation? 

The blood supply to the alveoli

28

What is the pulmonary circulation required for? 

Gas exchange

29

What must the pulmonary circulation accept? 

The entire cardiac output 

30

At what resistance does the pulmonary circulation work? 

Low

31

What allows the pulmonary circulation to work at low resistance? 

  • Short, wide vessels
  • Lots of capillaries connected in parallel 
  • Arterioles with relatively little smooth muscle 

 

32

What does the low resistance of the pulmonary circulation lead to? 

The circulation operating under low pressure

33

What is the mean pressure of the pulmonary artery? 

12-15mmHg

34

What is the mean pressure of the pulmonary capillaries? 

9-12mmHg

35

What is the mean pressure of the pulmonary veins? 

5mmHg

36

What must happen for efficient oxygenation? 

With respect to ventilation 

Ventilation of the alveoli need to be matched with perfusion 

37

What is the optimal ventilation/perfusion ratio? 

0.8

38

What is required to maintain the optimal ventilation/perfusion ratio? 

Diverting blood from alveoli that are less well perfused 

39

How is diversion of blood from less well perfused alveoli achieved? 

Hypoxic pulmonary vasconstriction

40

How does hypoxic pulmonary vasoconstriction achieve ventilation-perfusion matching? 

Alveolar hypoxia results in vasoconstriction of pulmonary vessels, and the increased resistance means less flow to the poorly ventilated areas and greater flow to well ventilated areas

41

What can chronic hypoxic vasoconstriction lead to? 

Right ventricular failure

42

Why can chronic hypoxic vasoconstriction lead to right ventricular failure? 

The chronic increase in vascular resistance puts a high afterload on the right ventricle, leading to its failure 

43

What is meant by the upper respiratory tract?

The parts of the respiratory tract lying outside the thorax

44

What components does the upper respiratory tract consist of? 

  • Nasal cavity 
  • Pharynx 
  • Larynx 

 

45

What is meant by the lower respiratory tract? 

Parts of the respiratory system lying inside the thorax

46

What components does the lower respiratory tract contain?

  • Trachea 
  • Main/primary bronchi 
  • Lobar bronchi 
  • Segmental bronchi 
  • Sub-segmental bronchi 
  • Bronchioles 
  • Termainal bronchioles
  • Respiratory bronchioles
  • Alveolar ducts 
  • Alveoli 

 

47

How many lobar bronchi are there? 

  • Three on right
  • Two on left 

 

48

What do bronchi have in their walls? 

Cartilage

49

How do bronchioles walls differ from those of bronchi?

  • No cartilage
  • More smooth muscle 

 

50

Label this diagram

 

Q image thumb

  • A - Nasal cavity 
  • B - Pharynx
  • C - Larynx
  • D - Trachea 
  • E - Primary bronchi
  • F - Lungs

 

51

What are the lungs a means of doing? 

Getting air to one side, and blood to the other, of a very thin membrane, with a large surface area

52

What structural features do the trachea and bronchi have? 

Cartilaginous rings 

53

Why do the trachea and bronchi have cartilaginous rings? 

In order to hold them open and provide a path for air to travel to the alveoli 

54

How do bronchioles draw air into the lungs?

By increasing their volume

55

How do bronchioles increase their volume?

Using the smooth muscle in their walls

56

What cells do alveoli have? 

  • Type I
  • Type II 

 

57

What type of cells are type I alveolar cells?

Simple squamous epithelia

58

What is the purpoes of type I alveolar cells?

Provide single cell thickness membrane for diffusion 

59

What is the purpose of type II alveolar cells? 

Produce surfactant to reduce surface tension of alveoli 

60

Where is the nose found? 

Superior to the hard palate

61

What is the nose comprised of? 

The external nose and nasasl cavity 

62

What is the nasal cavity divided into? 

Right and left cavities 

63

What divides the left and right cavities of the nasal cavity? 

The nasal septum 

64

What are the functions of the nose? 

  • Smelling
  • Respiration
  • Filtration of dust
  • Humidification of inspired air 
  • Reception and elimination of secretions from the paranasal sinuses and nasolacrimal ducts 

 

65

What happens to air passing over the respiratory area of the nose? 

It is warmed and moistened before it passes through the rest of the upper respiratory tract to the lungs 

66

What contains the peripheral organ of smell? 

The olfactory area 

67

What are the nasal conchae? 

Scroll-like structures

68

What are the nasal conchae also known as? 

Terbinates 

69

What are names of the nasal conchae? 

  • Superior
  • Middle
  • Inferior 

 

70

How do the nasal conchae sit? 

They curve inferiormedially, hanging like short curtains from the lateral wall of the nasal cavity 

71

What is the purpose of the nasal conchae?

They offer a vast surface area for heat exchange

72

Which concha is longest and broadest? 

The inferior 

73

What is the inferior concha formed by?

An independent bone (the inferior concha)

74

What are the middle and superior conchae formed from?

The medial processes of the Ethmoid bone 

75

What underlies each of the terbinates? 

A recess or nasal meatus 

76

What is the effect of the nasal meatus? 

It divides the nasal cavity into 5 passages 

77

Where does the sphenoethmoidal recess lie?

Superoposteiror to the superior conca

78

What does the sphenoethmoidal recess receive?

The opening of the sphenoidal sinus 

79

Label this diagram

 

Q image thumb

  • A - Ethmoidal crest of maxilla 
  • B - Atrium 
  • C - Lumen 
  • D - Nasal vestible 
  • E - Vibrissae (nasal hairs)
  • F - Spheno-ethmoidal recess
  • G - Superior nasal meatus 
  • H - Middle nasal meatus 
  • I - Inferior nasal meatus 
  • J - Nasopharynx

80

What are the paranasal sinuses? 

Air-filled extensions of the respiratory part of the nasal cavity into cranial bones

81

What are the sinuses named according to? 

The bones in which they are located

82

What are the names of the paranasal sinuses? 

  • Frontal 
  • Ethmoid
  • Sphenoid
  • Maxilla

 

83

Where are the right and left frontal sinuses located? 

Between the outer and inner tables of frontal bone, posterior to the superciliary arches and the root of the nose 

84

When are the frontal sinuses usally detectable? 

In children by 7 years of age 

 

85

How do the frontal sinuses drain? 

Each drain through a frontonasal duct 

86

Where do the frontal sinuses drain into? 

The ethmoidal infundibulum 

87

What does the ethmoidal infundibulum open into? 

The semilunar hiatus of the middle nasal recess

88

What are the ethmoidal cells (sinuses)?

Small invaginations of the mucuous membrane of the middle and superior nasal recesses into the Ethmoid bone 

89

When are the ethmoidal cells visible in plain radiographs? 

After 2 years of age 

90

Where do the anterior ethmoidal cells drain? 

Directly or indirectly into the middle nasal recess through the ethmoidal infundibulum 

91

Where do the middle ethmoidal cells open? 

Directly into the middle nasal recess 

92

Where do the posterior ethmoidal cells open? 

Directly into the superior nasal recess

93

Where are the sphenoidal sinuses located? 

In the body of the sphenoid, may extend into the wings of the bone 

94

Why may the sphenoidal sinuses be susceptible to injury? 

The body of the sphenoid is fragile, and only thin plates of bone seperate the sinuses from several important structures 

95

What structures are sepearated fron the sphenoidal sinuses by thin plates of bone? 

  • Optic nerves and chiasm 
  • Pituitary gland 
  • Internal carotid arteries 

 

96

Where do the sphenoidal sinuses drain? 

Directly into the sphenoethmoidal recess 

97

What are the largest of the paranasal sinuses? 

Maxillary sinuses 

98

What do the maxillary sinuses occupy?

The bodies of the maxillae 

99

How do the maxillary sinuses drain? 

By one or more openings, the maxillary ostium (ostia), into the middle nasal recess by way of the semilunar hiatus 

100

Label this diagram 

Q image thumb

  • A - Supra-orbital nerve
  • B - Frontal sinus 
  • C - Crista galli 
  • D - Superior oblique 
  • E - Medial rectus 
  • F - Ethmoidal infundibulum 
  • G - Ethmoidal air cells
  • H - Air cell in middle concha
  • I - Semilunar hiatus 
  • J - Middle meatus 
  • K - Opening of maxillary sinus 
  • L - Inferior minus 
  • M - Inferior concha 
  • N - Nasal septum 
  • O - Hard palate 
  • P - Oral cavity 
  • Q - Maxillary sinus 
  • R - Infra-orbital vessels and nerve 
  • S - Inferior rectus 
  • T - Inferior oblique 
  • U - Lateral rectus 
  • V - Eyeball 
  • W - Check ligament 
  • X - Lacrimal gland 
  • Y - Superior rectus 
  • Z - Levator palpebrae superioris 

 

101

Label this diagram 

Q image thumb

  • A - Frontal 
  • B & C - Ethmoidal 
  • D - Maxillary 
  • E - Sphenoidal 

102

What is the pharynx? 

The superior, expanded part of the alimentary system 

103

Where is the pharynx located? 

Posterior to the nasal and oral cavities, and extending inferiorly past the larynx 

104

Where does the pharynx extend?

From the cranial base to the inferior border of the cricoid cartilage anteriorly and the inferior border of the C6 vertebra posteriorly 

105

How wide is the pharynx at its widest point? 

~5cm

106

Where is the pharynx at its widest? 

Opposite the hyoid 

107

How wide is the pharynx at its narrowest point? 

~1.5cm 

108

Where is the pharynx at its narrowest?

At its inferior end, where it is continuous with the oesophagus 

109

What is the pharynx divided into? 

  • The nasopharynx 
  • The oropharynx
  • The laryngopharnx

 

110

Where is the nasopharynx found? 

Posterior to the nose and superior to the soft palate 

111

What kind of function does the nasopharynx have? 

Respiratory 

112

Why does the nasopharynx have a respiratory function? 

As it is the posterior extension of the nasal cavities 

113

What is formed around the superior part of the pharynx? 

A tonsillar ring 

114

What forms the tonsillar ring? 

Lymphoid tissue 

115

What does the tonsillar ring aggregate to form? 

Tonsils 

116

Where is the oropharynx found? 

Posterior to the mouth 

117

Where does the oropharynx extend? 

From the soft plate to the superior border of the epiglottis 

118

What kind of function does the oropharynx have? 

Digestive

119

What is the oropharynx involved in? 

Swallowing 

120

Where is the laryngopharynx found? 

Posterior to the larynx 

121

Where does the laryngopharynx end from? 

The superior border of the epiglottis to the inferior border of the cricoid cartilage

122

What happens to the laryngopharynx at the inferior border of the cricoid cartilage? 

It becomes continuous with the oesophagus 

123

Label this diagram 

 

Q image thumb

  • A - Nasopharynx 
  • B - Oropharynx 
  • C - Hypopharynx 
  • D - Oesphagus 
  • E - Sinus 
  • F - Nasal cavity 
  • G - Salivary glands
  • H - Oral cavity 
  • I - Trachea

124

Label this diagram

 

Q image thumb

  • A - Chona (posterior nasal aperture) 
  • B - Posterior lip of mouth of pharyngotympanic tube 
  • C - Pharyngeal recesses 
  • D - Salpingopharyngeal fold 
  • E - Terminal sulcus of tounge 
  • F - Pharyngo-epiglottic fold 
  • G - Aryepiglottic fold 
  • H - Piriform fossa (recess)
  • I - Thyroid gland 
  • J - Esophagus 
  • K - Pharyngo-esophageal junction (narrowest part of oesophagus)
  • L - Mucuous membrane covering cricoid cartilage 
  • M - Inferior pharyngeal constrictor (cut) 
  • N - Interarytenoid notch 
  • O - Laryngeal inlet (aditus)
  • P - Epiglottis 
  • Q - Middle pharyngeal constrictior (cut) 
  • R - Posterior 1/3 of tounge 
  • S - Foramen cecum 
  • T - Superior pharyngeal constrictor (cut)
  • U - Uvula 
  • V - Soft palate 
  • W - Nasal septum 
  • X - Cranial base 
  • Y - Body of sphenoid and basilar part of occipital bone 

 

  • I - Nasopharynx
  • II - Oropharynx
  • III - Laryngopharynx

125

What does the larynx connect? 

The inferior oropharynx to the trachea 

126

What does the larynx contain? 

The complex organ of voice production - the voice box

127

Where does the larynx extend? 

From the laryngeal inlet, through which it communicates with the laryngopharynx, to the level of the inferior border of the cricoid cartilage 

128

What is the laryngeal cavity continuous with at the level of the inferior border of the cricoid cartilage? 

The trachea 

129

What is the larynx's most vital function?

To guard the air passages, especially during swallowing

130

What does the larynx serve as during swallowing? 

The sphincter/valve of the lower respiratory tract, thus maintaining airway 

131

What does the voice box do? 

Controls sound production 

132

What is the voice box composed of? 

Nine cartilages, connected by membranes and ligaments containing the vocal folds

133

Label this diagram 

Q image thumb

  • A - Epiglottis 
  • B - Aryepiglottic fold 
  • C - Laryngeal vestibule 
  • D - Vestibular fold 
  • E - Thyroid cartilage 
  • F - Saccule 
  • G - Laryngeal ventricle 
  • H - Middle part of laryngeal cavity 
  • I - Vocal ligaments (opposed) 
  • J - Conus elasticus 
  • K - Infraglottic cavity 
  • L - Cricoid cartilage 
  • M - Trachea 

134

What is the tympanic cavity? 

The cavity of the middle ear- the narrow air-filled champer in the petrous part of the temporal bone 

135

What is the tympanic cavity connected with? 

  • Nasopharynx 
  • Mastoid cells 

 

136

In what direction is the nasopharynx connected with the tympanic cavity? 

Anteromedially 

137

How is the nasopharynx connected to the tympanic cavity? 

Via the pharyngotympanic (Eustachain) tube

138

In what direction is the tympanic cavity connected to the mastoid cells? 

Posterosuperiorly

139

How is the tympanic cavity connected to the mastoid cells? 

Via the mastoid antrum 

 

140

Label this diagram 

Q image thumb

  • A - Pinna 
  • B - Ossicles 
  • C - Auditory nerve 
  • D - Cochlea 
  • E - Eustachian tube
  • F - Ear drum 
  • G - Ear canal 

 

141

What membranes does the respiratory system contain? 

  • Mucuous membranes
  • Serous membranes

 

142

What do mucous membranes line in the respiratory system? 

The conducting portion of the respiratory tract 

143

What does the conducting portion of the respiratory tract bear? 

Mucus-secreting cells to varying degrees

144

What do serous membranes line in the respiratory tract? 

The pleural sacs that envelop each lung 

145

What are the types of epithelia found in the respiratory system? 

  • Psuedostratified, with cilia and goblet cells 
  • Simple columbar, with cilia and clara cells (but no goblet cells)
  • Simple cuboidal, with clara cells and cilia 
  • Simple squamous 

 

146

What areas of the respiratory system have psuedostratified epithelia with cilia and goblet cells? 

  • Nasal cavity
  • Pharynx
  • Larynx 
  • Trachea 
  • Primary and secondary bronchi 

 

147

What parts of the respiratory system have simple columnar epithelia with cilia and clara cells? 

  • Bronchioles
  • Terminal bronchioles

 

148

What parts of the respiratory system has simple cuboidal epithelia with clara cells and cilia? 

  • Respiratory bronchioles
  • Alveolar ducts 

 

149

What part of the respiratory system has simple squamous epithelia?

Alveoli 

150

What are the parts of the nasal cavity? 

  • Non-Olfactory regions 
  • Olfactory regions

 

151

What epithelia is found in non-olfactory regions of the nasal cavity? 

Pseudostratified ciliated

152

What is found in the lamina propria of non-olfactory regions of the nasal cavity? 

Mucous glands and venous sinuses 

153

What happens to the venous plexuses in the non-olfactory regions of the nasal cavity? 

They swell every 20-30 minutes 

154

What is the purpose of the swelling of the venous plexuses in the non-olfactory regions of the nasal cavity? 

Alternates air flow from side to side to prevent drying 

155

What is the effect of arterial blood in the non-olfactory regions of the nasal cavity? 

It warms inspired air 

156

What holds open the non-olfactory regions of the nasal cavity? 

Surrounding cartilage or bone 

157

What epithelium is found in the olfactory regions of the nasal cavity? 

Particularly thick pseudostratified epithelium

158

Are there goblet cells in the olfactory regions of the nasal cavity? 

No, therefore no mucus 

159

Where are the olfactory regions of the nasal cavity located? 

In the posterior, superior region of each nasal fossa 

160

What do the olfactory regions of the nasal cavity contain? 

  • Olfactory cells 
  • Bowman's glands 

 

161

What are olfactory cells? 

Bipolar neurons

162

What happens to the axons of olfactory cells? 

They join each other to form an olfactory nerve

163

What are Bowman's glands? 

Serous glands 

164

What is the purpose of Bowman's glands? 

Flush odorants from the epithelial surface 

165

Label this diagram 

Q image thumb

  • A - Microvilli
  • B - Olfactory vesicle 
  • C - Junctional complex 
  • D - Cilia
  • E - Supporting cell 
  • F - Axon
  • G - Basal cell 
  • H - Olfactory (Bowman's) gland
  • I - Olfactory cell 
  • J - Basal lamina 

166

What are the components of the larynx? 

  • Ventricular folds 
  • Vocal cords 

 

167

What are ventricular folds lined by? 

Pseudostratified epithelium 

168

What is the purpose of ventricles and their folds in the larynx? 

Give resonance to the voice 

169

What are vocal cords lined by? 

Stratified squamous epithelium 

170

What is the function of the vocal cord? 

  • Can stop foreign objects from reaching the lungs 
  • Close to build up pressure when coughing is required 

 

171

Label this diagram 

Q image thumb

  • A - False vocal cord
  • B - Ventricle 
  • C - True vocal cord 

 

172

What are the histological features of the trachea? 

  • Pseudostratified ciliated epithelium 
  • Lamina propria with many elastin fibres 
  • Seromucus glands 
  • C-shaped cartilage rings 

 

173

Label this histological slide 

Q image thumb

  • A - C-shaped cartilage ring 
  • B - Submucosa with seromucous glands 
  • C - Lamina propria 
  • D - Epithelium 

 

174

Label this histological slide 

 

Q image thumb

  • A - Oesophagus 
  • B - Cartilage 
  • C - Bone tissue 
  • D - Fibroelastic membrane 
  • E - Trachea 
  • F - Bone tissue 
  • G - Cartilage 

 

175

What are the primary bronchi histologically similar to? 

  • The trachea
  • Lobar and segmental bronchi 

 

176

How does the primary bronchi differ from the trachea? 

The cartilage rings completely encircle the lumen 

177

How do the lobar and segmental bronchi differ from the primary bronchi? 

Cartilage in cresent shapes, not a ring or completely encircling lumen 

178

Label this histological slide 

Q image thumb

  • A - Cartilage (cresent-shaped)
  • B - Epithelium (pseudostratified, ciliated) 
  • C - Smooth muscle 
  • D - Glands in submucosa 

 

179

What are the histological features of the bronchus? 

  • Small diameter 
  • Cartilage reduced to small islands 
  • Glands in submucosa 

 

180

Label this histological slide

Q image thumb

  • A - Pulmonary artery 
  • B - Bronchial artery 
  • C - Cartilage 
  • D - Bronchus 
  • E - Glands in submucosa
  • F - Bronchiole 

 

181

What are the histological features of the bronchioles? 

No cartilage or glands 

182

What keeps the bronchiole lumen open? 

Surrounding alveoli 

183

What happens as bronchioles get smaller? 

With respect to goblet cells

Goblet cells give way to clara cells 

184

Where are clara cells found? 

Interspersed between ciliated cubiodal cells 

185

What do clara cells do? 

Secrete a surfactant lipoprotein and protein CC16

186

What is the purpose of the surfactant lipoprotein secreted by clara cells? 

It prevents the walls sticking together during expiration 

187

What is the clinical importance of protein CC16? 

It is a measurable marker in bronchoalveolar damage or leakage across the air-blood barrier

188

What does lowered CC16 indiciate? 

Lung damage 

189

What does raised CC16 indicate? 

Leakage across barrier 

190

Label this diagram of a Clara cell 

Q image thumb

  • A - Secretory vesicles 
  • B - Golgi apparatus 
  • C - rER
  • D - Nucleus 
  • E - Junctional complex
  • F - sER
  • G - Mitochondrion 
  • H - Basal lamina 

 

191

Why is absence of goblet cells in the terminal bronchiole important? 

To prevent individuals 'drowning' in their own mucus 

192

What distinguishes bronchi from bronchioles?

  • Cartilage
  • Glands 
  • Differing diameters distinguishes 

 

193

Do terminal bronchioles have alveolar openings? 

No 

194

Do respiratory bronchioles have alveolar openings? 

Bronchiole wall opens onto some alveoli 

195

Do alveolar ducts have alveolar openings?

Duct wall has openings everywhere onto alveoli 

196

What is an alveolus? 

A single alveoli 

197

What is the alveolar sac? 

Composite air space onto which many alveoli open 

198

What are the features of the structure of the alveoli? 

  • Abundant capillaries 
  • Supported by basketwork of elastic and reticular fibres
  • Covering composed chiefly of type I pneumocytes 
  • Scattering of interventing type II pneumocytes 
  • Macrophages line alveolar surface

 

199

What shape are type I pneumocytes? 

Simple squamous 

200

What % of the alveoli surface area is covered by type I pneumocytes? 

90%

201

What do type 1 pneumocytes permit? 

Gas exchange with capillaries 

202

What shape are type II pneumocytes? 

Simple cuboidal 

203

What do type II pneumocytes do? 

Produce surfactant 

204

What % of the alveoli surface area is covered by type II pneumocytes? 

10% 

205

What is the purpose of the macrophages lining the alveolar surface? 

To phagocytose particles 

206

When can new alveoli develop up to? 

8 years old 

207

How many alveoli are there at 8 years old? 

300,000,000

208

What can alveoli open into? 

  • A respiratory bronchile 
  • An alveolar duct or sac
  • Another alveolous (via an alveolar pore)

 

209

Label this histological slide 

Q image thumb

A image thumb
210

Label this diagram 

Q image thumb

  • A - Smooth muscle 
  • B - Alveolus 
  • C - Capillaries 
  • D - Elastic fibres 

 

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What is this photomicrograph showing? 

Q image thumb

Alveolar sac with adjacent alveoli