Structure of the airway and lungs Flashcards
Aidan (120 cards)
1
Q
What are the structures in the respiratory tract?
A
- Nose, nasal cavity and sinuses.
- Nasopharynx and soft palate.
- Larynx.
- Trachea.
- Bronchi and bronchial tree.
- Lungs and pleura.
- Thoracic wall.
- Diaphragm.
2
Q
What is respiration?
A
Providing oxygen to the body and removing carbon dioxide through inhalation and exhalation.
3
Q
Is the air in the lungs of atmospheric composition or not?
A
The air in the lungs is not of atmospheric composition and may even change between different areas of the lung
4
Q
What must air that is brought into the lungs be?
A
Must be warmed, filtered and humidified.
5
Q
What structures warm, filter and humidify inhaled air?
A
Vascular, mucosa, cilia, mucus.
6
Q
What are the conductive passages of the respiratory system?
A
Nasal cavity; nasopharynx; larynx; trachea; bronchi.
7
Q
How is air sucked down the conductive passages and into the lungs?
A
By creating negative intra-thoracic pressure.
8
Q
What happens in the body during inhalation?
A
Contraction (and lowering) of the diaphragm and raising the ribs
9
Q
Why does inhaling expend energy?
A
It expends energy as you are contracting muscles.
10
Q
Why is air in the lungs not of atmospheric composition?
A
Mainly due to gas exchange.
11
Q
How is exhalation achieved?
A
By decreasing the size of the thorax, this is generally a passive process. (Almost no energy expended).
12
Q
What is the name of the external structure that encloses the nasal cavities?
A
The nose.
13
Q
How is the nasal cavity entered?
A
Via the nares.
14
Q
What holds the nasal cavities open?
A
Bone and cartilage.
15
Q
What is the start of the respiratory tract?
A
The nasal cavities.
16
Q
What are the nasal cavities lined with?
A
A highly vascularised mucosal membrane lined with respiratory epithelium.
17
Q
How would you describe respiratory epithelium?
A
Psuedostratified, ciliated, columnar and interspersed with goblet cells.
18
Q
Are the cells that line the nasal cavity, respiratory tract and mouth one and the same?
A
No, the cells in the nasal cavity are different from the ones in the rest of the respiratory tract and mouth.
19
Q
What is the nasal septum?
A
A midline structure which separates the left and right nasal cavities.
20
Q
Describe the structure of the septum.
A
Anteriorly the septum is made of septal cartilage, while posteriorly the septum is made of bone.
21
Q
What could be a problem that occurs if the septum deviated from the midline?
A
Sinus drainage may be compromised.
22
Q
What structure forms the medial boundary of the nasal cavities?
A
The nasal septum.
23
Q
What structure forms the floor boundary of the nasal cavities?
A
The hard and soft palates.
24
Q
What structure forms the roof boundary of the nasal cavities?
A
Bone. (ethmoid, frontonasal, sphenoid).
25
What structure forms the lateral boundary of the nasal cavities?
The nasal conchae.
26
Which palate is posterior and anterior in the nasal cavity?
The hard palate is anterior and the soft palate is posterior.
27
What position is the floor of the nasal cavity in?
Horizontal. (Due to placement of the nasogastric tube).
28
Where is incoming air prepared to enter the lungs? (i.e. filtered, warmed etc.).
It is acclimatised in the nasal cavity.
29
Where are the nasal conchae located?
They are located on the lateral wall of the nasal cavity.
30
What are the names of the three conchae?
Superior, middle and inferior.
31
What do the nasal conchae do?
Provide turbulence and increase the surface areas for airflow and heat exchange.
32
Which of the meati allow access to the maxillary sinus?
The middle meatus.
33
What is positioned under each concha in the nasal cavity?
An empty space called a meatus.
34
Where do air sinuses open into?
They open up into their adjacent meatus
35
What is the space above the superior concha called?
The Spheno-ethmoidal recess.
36
What are the structures of the nasal cavity?
- Septum.
- Lateral walls with conchae.
- Meati
- The airway
37
What are the purpose of the sinuses?
They are empty spaces structurally so they reduce the weight of the skull, they also increase the space in which you can warm air in.
38
Why is the clearance of mucus in the maxillary sinus dependant on ciliary action?
As the opening is high in its medial wall.
39
What can happen if ciliary action is compromised by infection?
The mucus in the maxillary sinus cannot be cleared and can possibly lead to sinusitis.
40
What else may predispose you to sinusitis?
A deviated septum.
41
What is the problem with the space between the septum and the conchae in the nasal cavity?
It is quite narrow so if inflammation or increased production of mucus occurs it can cause pressure and pain.
42
Where does the nasolacrimal duct enter and what does it do?
The nasolacrimal duct enters the nasal cavity to drain tears from the conjuctunctiva of the eye.
43
What are the four main sinuses in the cranium?
- Frontal sinus.
- Ethmoidal (air cells).
- Maxillary Sinus.
- Sphenoidal sinus.
44
Is the nasal cavity mucosa high vascularised or not highly vascularised?
It is highly vascularised.
45
What is notable about the vessels in the nasal cavities vascular mucosa?
The vessels anastamose between branches of the external carotids and internal carotids (both left and right).
46
Why are the nasal cavities vessels so easy to rupture?
They are close to the surface.
47
Where are the olfactory nerves located?
As the olfactory bulb in the roof (and upper parts of lateral wall) of the nasal cavity.
48
What is the pharynx?
It is a tube of fibrous and muscular tissue that can be divided into three parts.
49
What are the names and locations of the three parts of the pharynx?
- Nasal cavity (nasopharynx).
- Oral cavity (oropharynx).
- Larynx (laryngopharynx).
50
What does the nasopharynx do?
```
Transport air (thats it).
It is divided from the oropharynx by the soft palate.
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51
What does the oropharynx do?
It transports food and air and fluid.
52
Where do food and fluid go after passing through the oropharynx?
They continue into the laryngopharynx.
53
Where does air go after passing through the oropharynx?
It passes into the larynx.
54
How are aspiration pneumonia's caused?
They are caused by food or fluid that has gotten into the lungs and caused a pneumonia.
55
What is the ary-epiglottic fold?
The muscles that allow you to close your epiglottis.
56
What is the larynx?
It is a membranous tube suspended between cartilages, the positions of which are controlled by muscles.
57
How may the larynx be altered and what does this allow?
The laryngeal diameters may be altered to allow the passage of air (only), and to control airflow for speech and raising intra-abdominal pressure.
58
What is unusual about the hyoid bone?
It is the only bone in the body not connected to any other bone structure.
59
What is the Cricothyroid membrane used for in emergency situations?
As a site of emergency access to the airway.
60
What is the makeup of the laryngeal cartilages?
Overall there is one bone and nine bits of cartilage (most of which are paired).
61
What are the Arytenoids and corniculates and where do they sit?
They are small pieces of cartilage that sit on top (posteriorly) of the cricoid arch (made of cartilage).
62
What is the quadrangular membrane important for?
It is important for sealing the larynx over.
63
What structure is at the upper edge of the quadrangular membrane?
The Aryepiglottic fold is at the upper edge of the quadrangular membrane.
64
What structure is at the lower end of the quadrangular membrane?
The vestibular fold is at the lower edge of the quadrangular membrane.
65
Where is the vocal fold located?
On the upper edge of the cricovocal/cricothyroid membrane.
66
What structure do the ary-epiglottal folds form and what does that structure do?
They form the laryngeal inlet, which is the protective sphincter.
67
How does the closure of the laryngeal inlet occur?
Closure of the inlet is by elevation of the larynx, which is lifted up and forward during swallowing.
68
What do muscles in the ary-epiglottic folds aid with?
They aid with both the closure and widening of the laryngeal inlet.
69
What is located within the opening of the laryngeal ventricle?
It is the saccule where there are mucosal glands which help lubricate the vocal folds.
70
Why do the vocal folds control laryngeal diameter?
For coughing, sneezing, speech and raising the intra-abdominal pressure (vital in micturition, defecation and lifting heavy objects).
71
What is the name of the opening in the vocal folds?
The rima glottidis.
72
What are the main actions of laryngeal muscles?
- Close/open the inlet (ary-epiglottic folds).
- Close/open the rima glottis (arytenoid gliding and rotation).
- Shorten/lengthen the vocal folds ('rocking' at cricothyroid joints).
73
What nerves in the larynx do you have to be not to damage in surgical interventions.
Superior laryngeal nerve and right/left recurrent laryngeal nerve.
74
What does the superior laryngeal nerve do?
Supplies only one muscle and sensation above the vocal cords.
75
What does the recurrent laryngeal nerve do?
Supplies all other muscles the superior laryngeal nerve doesn't, it also supllies sensation of vocal cords and below.
76
Where is the trachea located?
In front of the oesophagus, ,medial to carotid arteries and internal jugular veins, inferior to larynx and the upper portion is surrounded by the thyroid gland.
77
What do the trachea divide into?
It divides into the right and left bronchi.
78
What is anatomical dead space?
Parts of the respiratory system that have air in them and are measured in lung function tests but don't take part in gas exchange.
79
Where is anatomical dead space located in the respiratory tract?
Everything above respiratory bronchioles is anatomical dead space (no gas exchange function).
80
What shape are hyaline cartilage?
They are C-shaped.
81
What vertebrae does the trachea start and end with?
Starts at C6 ands at T4/5.
82
What muscle is responsible for altering tracheal diameter?
Trachealis muscle.
83
which lung is more likely to have foreign objects enter it?
The right lung.
84
How many lobes on each lung?
Two lobes on the left lung and three on the right.
85
Why are foreign objects more likely to enter the right lung?
the entrance is slightly more vertical, shorter and wider so it is easier to get into right bronchi.
86
How are bronchi supplied with oxygenated blood?
The bronchial arteries.
87
How many lobar bronchi does the right lung have?
It has three secondary lobar bronchi. (superior, middle and inferior).
88
How many lobar bronchi does the left lung have?
It has two secondary lobar bronchi. (superior and inferior).
89
How to bronchi divide?
Smaller and smaller branches; bronchi, conducting bronchioles then terminal bronchioles and then respiratory bronchioles, decreasing along the way until finally becoming alveoli.
90
What are the characteristics of the trachea's histology?
Psuedostratified, ciliated columnar epithelium, with goblet cells for mucous secretion.
91
Volume of mucus produced per day?
Roughly one litre.
92
What are the characteristics of the bronchi's histology?
still psuedostratified, ciliated columnar epithelium but the height is decreased (flattened) compared to the trachea.
93
What replaces the C-shaped cartilage rings as the bronchi branch into the lungs?
The rings are replaced by cartilage plates.
94
Describe the endothelium of the bronchioles?
Ciliated columnar (thinner/flatter) and there is a surrounding band of smooth muscle
95
What changes from the bronchi to bronchiole?
The cartilage and glands disappear and the bronchiole is instead held open by the surrounding lung tissue.
96
What happens in asthma?
The smooth muscle in the wall of the bronchioles may excessively narrow the lumen.
97
Describe the epithelium of the terminal and respiratory bronchioles.
Non-ciliated cuboidal (thinner and flatter) and goblet cells disappear.
98
What does the thinner epithelium in the terminal and respiratory bronchioles make easier?
It makes gas exchange easier.
99
What are alveoli?
They are the basic structural and functional unit of the lung where gaseous exchange occurs.
100
How are alveoli seperated from each other?
By septae (thin membrane containing capillaries).
101
What are septae?
It is the air-blood barrier for gas exchange and its a thin membrane containing capillaries.
102
What are pleura?
They are the membranes which cover/lines the organs (lungs) within the cavities as well as the cavity walls.
103
What would happen without pleura?
The lungs would collapse.
104
What is the visceral/pulmonary pleura?
the pleura covering the lungs.
105
What are parietal pleura?
The membranes which line the cavity walls.
106
What are the different names of the parietal pleura?
cervical, costal, mediastinal and diaphragmatic
107
Why are pleural cavities under negative pressure?
These are all under negative pressure in this pleural cavity so the elastic lung inflates to fill the space, if air got into this space then the lung would collapse as there would be no vacuum any longer.
108
Why is the left lung slightly longer and narrower than the right one?
This is mainly to make room for the heart and pericardium.
109
what are the cardiac notch and the lingula present in the left lung for?
To provide space for the heart.
110
What is the hilium?
The 'root of the lung' where structures such as the pulmonary artery, main bronchus etc. enter and exit the lung.
111
What is unusual about the bloodflow in the short circuit between the lungs and heart?
veins are carrying oxygenated blood and arteries are carrying deoxygenated blood (the is the only case where this happens).
112
What is different about the right lung?
It is slightly wider and shorter than the left.
113
Where can the lung sometimes extend above?
Can sometimes extend above the collarbone, but under normal circumstances the air in the lung is rarely so full that the lung extends this far.
114
What can you tell by the position of the trachea? (if it is in an unusual position).
If the trachea has shifted from its normal position you can tell a variety of conditions from where it has shifted to (collapsed lung etc.).
115
What do the internal intercostal muscles have to do with respiration?
They depress the ribs, pulling them interiorly as in deep exhalation.
116
What do the external intercostal muscles have to do with respiration?
They elevate and lift the ribs as in deep inhalation.
117
What do the intercostal muscles do?
They assist in respiration by expanding the size of the thoracic cavity during inspiration and may also assist in forced expiration to help lower the ribs.
118
describe the structure of the diaphragm.
muscular at the periphery and tendinous centrally with right and left domes
119
What supplies motor and sensory to the diaphragm?
The phrenic nerve (C3, 4, 5).
120
What causes a pneumothorax?
Air enters into the pleural cavity which causes the vacuum to disappear and the lung to collapse.
