Chr. 23 - The Respiratory system Flashcards
(169 cards)
1
Q
[23.1] What is respiration?
A
The process of supplying the body with oxygen and removing carbon dioxide.
2
Q
[23.1] What are the steps of respiration?
A
- Pulmonary ventilation
- External respiration
- Internal respiration
3
Q
[23.1] What is pulmonary ventilation?
A
Inhalation and exhalation of air and the gas exchange between atmospheric air and alveoli.
4
Q
[23.1] What is external respiration?
A
Gas exchange between alveolar tissue and blood within the pulmonary circuit.
5
Q
[23.1] What is internal respiration?
A
Gas exchange between blood cells and cell tissue/intercellular fluid at capillaries.
6
Q
[23.1] List the components of the respiratory system.
A
- Nose
- Pharynx
- Larynx
- Trachea
- Bronchi
- Lungs
7
Q
[23.1] What components of the respiratory system compose the upper respiratory system?
A
Nose, nasal cavity, pharynx, and associated structures
8
Q
[23.1] What components of the respiratory system compose the lower respiratory system?
A
Larynx, trachea, bronchi, and lungs.
9
Q
[23.1] What is the conducting zone of the respiratory system?
A
A functional division of the respiratory system consisting of a series of interconnecting cavities and tubes outside and inside the lungs where air moves.
10
Q
[23.1] What is the purpose of the conducting zone of the respiratory system?
A
Filter, warm, and moisten air conducted into the lungs.
11
Q
[23.1] What is the respiratory zone of the respiratory system?
A
A functional division of the respiratory system consisting of tubes and tissues within the lungs where gas exchange occurs.
12
Q
[23.1] List the functions of the respiratory system.
A
- Provides sites of gas exchange
- Regulates blood pH
- Contains receptors for smell
- Produces vocal sounds
- Excretes heat and water
- Filters air
13
Q
[23.2] Describe the nose.
A
A specialized organ at the entrance of the respiratory system, divided into external and internal. The external nares are the openings in which air first passes, and the nasal vestibules are the cavities that air passes through.
14
Q
[23.2] What are the frameworks of the nose?
A
Bony and cartilaginous.
15
Q
[23.2] What composes the bony framework of the nose?
A
Frontal bone, nasal bone, and maxillae.
16
Q
[23.2] What composes the cartilaginous framework of the nose?
A
Septal nasal cartilage, lateral nasal cartilages, and (major/minor) alar cartilages.
17
Q
[23.2] What is the nasal cavity?
A
The large space in the anterior aspect of the skull. Superior to oral cavity and inferior to the nasal bone.
18
Q
[23.2] What is the nasal septum?
A
A vertical partition dividing the nasal cavity into right and left sides.
19
Q
[23.2] What are the internal nares?
A
Two openings merging the nasal cavity and the pharynx.
20
Q
[23.2] What are the paranasal sinuses?
A
Sinuses draining mucus into the nasal cavity.
21
Q
[23.2] What are nasolacrimal ducts?
A
Ducts draining lacrimal fluid into the nasal cavity.
22
Q
[23.2] What is the respiratory region of the nose?
A
A larger, inferior region lined with ciliated pseudostratified columnar epithelium and goblet cells. Known as respiratory epithelium.
23
Q
[23.2] What is the olfactory region of the nose?
A
A smaller, superior region of the nasal cavity responsible for olfaction and containing olfactory epithelium.
24
Q
[23.2] What is the nasal vestibule?
A
The anterior portion of the nasal cavity surrounded by cartilage.
25
[23.2] What are the superior, middle, and inferior nasal conchae?
Shelf-like projections extending from the lateral wall of the nasal cavity.
26
[23.2] What are the superior, middle, and inferior nasal meatuses?
Subdivisions of the respective nasal conchae forming groove-like air passageways lined by mucous membranes and serving to increase surface area.
27
[23.2] What is the pharynx?
A funnel-shaped tube starting at the internal nares and extending to the level of cricoid cartilage. Lays posterior of nasal/oral cavities, superior of larynx, and anterior of cervical vertebrae.
28
[23.2] List the functions of the pharynx.
1. Passageway for food and air
2. Acts as resonating chamber for speech and sound
3. Houses tonsils
29
[23.2] What are the anatomical regions of the pharynx?
1. Nasopharynx
2. Oropharynx
3. Laryngopharynx
30
[23.2] Describe the nasopharynx.
The superior portion, laying posterior of nasal cavity and extending to the soft palate.
31
[23.2] What is the soft palate?
The posterior roof of the mouth, an arch-shaped muscular partition separating nasopharynx and oropharynx.
32
[23.2] What are the openings of the soft palate?
Two internal nares, two auditory tube openings, and the opening to the oropharynx.
33
[23.2] What is the pharyngeal tonsil?
A tonsil residing in the posterior wall of the soft palate.
34
[23.2] Describe the oropharynx.
Intermediate portion of the pharynx extending from soft palate to the hyoid bone. Lined with nonkeratinized stratified squamous epithelium.
35
[23.2] What is the fauces?
The opening of the oropharynx.
36
[23.2] What are the tonsils found in the oropharynx?
The palatine tonsils and lingual tonsils.
37
[23.2] Describe the laryngopharynx.
Portion of the pharynx beginning at the hyoid bone and ending at the esophagus and larynx. Nonkeratinized stratified squamous epithelium.
38
[23.3] Describe the larynx.
A short passageway connecting the pharynx with the trachea and houses nine pieces of cartilage.
39
[23.3] What are the nine pieces of cartilage found in the larynx?
Singular: Thyroid cartilage, epiglottis, and cricoid cartilage.
Paired: arytenoid, cuneiform, and corniculate.
40
[23.3] What is the cavity of the larynx.
The space extending from the entrance into the larynx to the inferior border of the cricoid cartilage.
41
[23.3] What is the laryngeal vestibule?
The portion of the cavity of larynx above the vestibular folds.
42
[23.3] What is the infraglottic cavityof the larynx?
The portion of the cavity below the vocal folds.
43
[23.3] What is the thyroid cartilage?
Two fused plates of hyaline cartilage forming the anterior wall of the larynx. Triangular in shape.
44
[23.3] What is the epiglottis?
A large, leaf shaped piece of elastic cartilage covered in epithelium closing either the larynx or the pharynx depending on the action; swallowing raises the pharynx and closes the larynx, and breathing elevates the larynx and closes the pharynx.
45
[23.3] What is the glottis?
A structure consisting of a pair of folds of mucous membranes, the vocal folds, and the space between known as the rima glottidis.
46
[23.3] What is the cricoid cartilage?
A ring of hyaline cartilage forming the inferior wall of the larynx.
47
[23.3] What are the arytenoid cartilages?
Paired triangular hyaline cartilages at the posterior and superior border of the cricoid cartilage.
48
[23.3] What are the corniculate cartilages?
Horn-shaped elastic cartilages located at the apex of each arytenoid cartilage.
49
[23.3] What are the vestibular folds?
The superior pair of folds within the mucous membrane of the larynx, also known as the false vocal cords.
50
[23.3] What are the vocal folds?
Inferior pair of folds within the mucous membrane of the larynx, also known as the true vocal cords.
51
[23.3] What is the rima vestibuli?
The space between the vestibular folds.
52
[23.3] What is the laryngeal ventricle?
A lateral expansion of the middle portion of the laryngeal cavity between the vestibular and vocal folds.
53
[23.3] What are the principal structures of voice production?
The vocal folds.
54
[23.3] Describe the trachea.
A tubular passageway appr. 12cm long and 2.5cm in diameter. Found anterior of esophagus and extends from the larynx to the superior border of T5.
55
[23.3] List the layers of the tracheal wall from deep to superficial.
1. Mucosa
2. Submucosa
3. Hyaline cartilage
4. Adventitia
56
[23.3] What are the bronchi?
Divisions of the trachea as it branches into the left and right lungs via the left bronchus and right bronchus respectively.
57
[23.3] What is the carina?
An internal ridge defining the division of the trachea into the left and right bronchus.
58
[23.3] What are lobar bronchi?
Passageways branching off the main bronchus into lobes of the lung, forming the primary branches that smaller bronchi branch from.
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[23.3] What are segmental bronchi?
Branches off the lobar bronchi supplying bronchopulmonary segments within lobes.
60
[23.3] What are bronchioles?
Divisions of segmental bronchi.
61
[23.3] What are terminal bronchioles?
Divisions of bronchioles that exist at the end of the conducting zone and branch into alveoli ducts. Contain club cells.
62
[23.3] What are club cells?
Nonciliated columnar cells interspersed among epithelial cells protecting against toxins and carcinogens, producing surfactant, and acting as stem cells.
63
[23.3] What is the bronchial tree?
The extensive structure beginning with the trachea and including all passageways down to terminal bronchioles.
64
[23.3] Briefly describe the lungs.
Paired, cone-shaped organs in the thoracic cavity, divided into their own cavities by the mediastinum. Protected by double-layered serous membrane called the pleural membrane.
65
[23.3] List and describe the layers of the pleural membrane.
1. The parietal pleura, lining the wall of the thoracic cavity
2. The visceral pleura, lining the lungs themselves
3. The pleural cavity, the space between the parietal and visceral pleura and containing pleural fluid.
66
[23.3] List and describe notable anatomical landmarks of the lungs.
- Base, the inferior portion of the lung
- Apex, the narrow superior portion of lung resting superior of the clavicle
- The costal surface, surface of the lungs facing the ribs and matching curvature
- The mediastinal surface, surface of the lung facing the mediastinum
- Hilum, the region on each lung through which bronchi, pulmonary blood vessels, lymph vessels and nerves enter and exit
- The root, composed of pleura and connective tissue containing structures passing through the hilum
- The cardiac notch, a concavity of the left lung accommodating the heart
67
[23.3] What are fissures of the lungs?
Fissures separating the lung into lobes.
68
[23.3] List the fissures of each lung.
Right lung: oblique fissure, horizontal fissure
Left lung: oblique fissure
69
[23.3] List the lobes of each lung.
Right lung: Superior lobe, middle lobe, inferior lobe
Left lung: Superior lobe, inferior lobe
70
[23.3] What is a bronchopulmonary segment?
The portion of lung tissue supplied by a segmental bronchus
71
[23.3] What are lobules of the lung?
Small compartments of bronchopulmonary segments wrapped in connective tissue and containing a lymph vessel, arteriole, venule, and a branch of a terminal bronchiole.
72
[23.3] What are respiratory bronchioles?
Subdivisions of terminal bronchioles containing alveolar ducts and thus initiating the respiratory zone.
73
[23.3] What are alveolar ducts?
Subdivisions of respiratory bronchioles.
74
[23.3] What is an alveolar sac?
A terminal dilation of an alveolar duct and shaped like a cluster of grapes.
75
[23.3] What are alveoli?
Individual pouches within an alveolar sac containing type I and type II alveolar cells.
76
[23.3] Describe type I alveolar cells.
Simple squamous epithelial cells forming the lining of the wall and acting as main sites of gas exchange.
77
[23.3] Describe type II alveolar cells.
Cuboidal epithelial found interspersed within type I alveolar cells and responsible for secreting alveolar fluid.
78
[23.3] What is surfactant?
A mixture of phospholipids and lipoproteins lowering surface tension of alveolar fluid and thus reducing probability of alveolar collapse.
79
[23.3] What are alveolar macrophages?
Phagocytes found within the alveolar wall removing dust particles and debris.
80
[23.3] What is the respiratory membrane?
A membrane formed by alveolar walls and capillary walls where exchange of oxygen and carbon dioxide occurs through diffusion.
81
[23.3] List the four layers of the respiratory membrane.
1. Alveolar wall
2. Epithelial basement membrane of alveolar wall
3. Capillary basement membrane
4. Capillary endothelium
82
[23.3] Describe the flow of blood supply to the lungs.
Blood flows from the heart to the lungs through pulmonary trunk, splitting into left and right pulmonary arteries that branch into bronchial arteries and eventually forming capillaries adjacent to alveoli. Blood then leaves the capillaries and enters the pulmonary veins and returns to the heart.
83
[23.3] Describe ventilation-perfusion coupling.
The reversal of the effects of hypoxia on blood vessel within the lungs. Typically, hypoxia induces vasodilation. In blood vessels of the lungs, hypoxia induces vasoconstriction, diverting blood from poorly ventilated areas and into better ventilated areas.
84
[23.3] What is patency of the respiratory system?
The effectiveness and efficiency of the respiratory system to carry out its function.
85
[23.4] What is pulmonary ventilation?
The flow of air between the atmosphere and the lungs/alveoli.
86
[23.4] What is inhalation?
Intake of air into the lungs from the atmosphere.
87
[23.4] Describe Boyle's law.
Boyle's law states the pressure of gas in a closed container is inversely proportional to volume. As volume increases, pressure decreases, and vice versa.
88
[23.4] How does Boyle's law apply to breathing?
At rest, air pressure in the lungs is equal to pressure in the atmosphere. On inhalation, thoracic volume and thus lung volume increases. Boyle's law states that as volume increases, pressure drops. When pressure in the lungs drops, the atmospheric pressure, which is higher, pushes air into the lungs to equalize the difference. On exhalation, lung volume decreases as muscles relax to resting position, increasing lung pressure and forcing air into the atmosphere.
89
[23.4] What is intrapleural pressure?
The pressure within the pleural cavity and is always lower than atmospheric pressure. This creates a vacuum and causes the visceral pleura to adhere to the parietal pleura.
90
[23.4] What is alveolar pressure?
The pressure of air within the alveoli, and is the pressure measured against atmospheric pressure during inhalation/exhalation.
91
[23.4] What is exhalation?
A passive process where muscles relax and elastic recoil of the chest and lungs increases thoracic pressure, expelling air.
92
[23.4] What are the two factors affecting elastic recoil of the lungs?
1. The integrity of elastic fibers stretched during inhalation producing recoil
2. Inward pull of surface tension generated by intrapleural fluid within the pleural cavity.
93
[23.4] What is surface tension?
Tension at surfaces of water exposed to air generated by the attraction of polar molecules to other polar molecules within water.
94
[23.4] What is compliance of the lungs?
The effort required to stretch the lungs and chest walls; high compliance means less effort required to expand, low compliance means greater effort required to expand.
95
[23.4] What is airway resistance?
The factors affecting resistance of airflow through the lungs. Smaller airways increase resistance, as well as obstructions.
96
[23.4] What is eupnea?
Normal, quiet pattern of breathing.
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[23.4] What is costal breathing?
A pattern of shallow breathing due to contraction of external intercostal muscles.
98
[23.4] What is diaphragmatic breathing?
A pattern of deep breathing due to outward movement of the abdomen from contraction of diaphragm.
99
[23.4] List the modified breathing patterns.
1. Coughing
2. Sneezing
3. Sighing
4. Yawning
5. Sobbing
6. Crying
7. Laughing
8. Hiccupping
9. Valsalva maneuver
10. Pressurizing of middle ear
100
[23.4] Describe coughing.
Long, deep inhalations followed by complete closure of rima glottidis, forcing a strong exhalation.
101
[23.4] Describe sneezing.
Spasmodic contraction of exhalation muscles forcefully expelling air through nose and mouth.
102
[23.4] Describe sighing.
Long, deep inhalation followed by a short yet forceful exhalation.
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[23.4] Describe yawning.
A deep inhalation producing exaggerated depression of mandible.
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[23.4] Describe sobbing.
Convulsive inhalations followed by a single prolonged exhalation. Rima glottidis closes early on inhalations causing short inhalations.
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[23.4] Describe crying.
Single inhalation followed by short, convulsive exhalations. Rima glottidis remains open and vocal folds vibrate.
106
[23.4] Describe laughing.
Single inhalation followed by short convulsive exhalations, but different rhythm to movements than crying.
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[23.4] Describe hiccuping.
Spasmodic contraction of the diaphragm accompanied by spasmodic closure of rima glottidis, producing a sharp sound on inhalation.
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[23.4] Describe valsalva maneuver.
Forced exhalation against a closed rima glottidis leading to increased thoracic and intracranial pressure.
109
[23.4] Describe pressurizing the middle ear.
Forced exhalation while closing mouth and nose, forcing air into the eustachian tube into the middle ear and equalizing pressure in the middle ear with the atmosphere.
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[23.5] What are lung volumes?
Measurements of the amount of air moved or remaining during different breathing actions.
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[23.5] What are lung capacities?
Combinations of different lung volumes.
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[23.5] List the lung volumes.
1. Tidal volume
2. Inspiratory reserve volume
3. Expiratory reserve volume
4. Residual volume
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[23.5] What is tidal volume?
The volume of a normal breath of an individual.
114
[23.5] What is inspiratory reserve volume?
The additional air taken in during a deep inhalation.
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[23.5] What is expiratory reserve volume?
The amount of air that is expelled from the lungs during a forced expiration after a normal inhalation.
116
[23.5] What is "forced expiratory volume in 1 second"?
The volume of air exhaled during 1 second during a forceful exhalation after a forced inhalation.
117
[23.5] What is residual volume?
The air remaining in non-collapsible airways that cannot be moved after forced exhalation.
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[23.5] What is anatomic dead space?
The region of conducting airways containing air that does not participate in gas exchange.
119
[23.5] List the lung capacities.
1. Inspiratory capacity
2. Functional residual capacity
3. Vital capacity
4. Total lung capacity
120
[23.5] What is inspiratory capacity?
The sum of tidal volume and inspiratory reserve volume.
121
[23.5] What is functional residual capacity?
The sum of residual volume and expiratory reserve volume.
122
[23.5] What is vital capacity?
The sum of inspiratory reserve volume, tidal volume, and expiratory reserve volume.
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[23.5] What is total lung capacity?
The sum of vital capacity and residual volume, or all four lung volumes.
124
[23.5] What is minimal volume?
The air remaining in the lungs after the thoracic cavity is opened and the intrapleural pressure equalizes with atmospheric pressure.
125
[23.5] What is minute ventilation?
The total volume of air inspired and expired each minute.
126
[23.5] What is alveolar ventilation?
The volume of air per minute reaching the respiratory zone.
127
[23.6] Explain Dalton's law.
The textbook reports that Dalton's law states that the gas present in a mixture exerts pressure as if no other gasses are present.
Dalton's law, really, is that the total pressure of a mixture of gasses is equal to the sum of partial pressures of all gasses within the mixture.
128
[23.6] What is partial pressure?
The pressure exerted by a specific gas within a mixture.
129
[23.6] Explain Henry's law.
Henry's law states that the quantity of gas that will dissolve in a liquid is proportional to the partial pressure of the gas as well as its solubility.
130
[23.6] What is external respiration?
The diffusion of oxygen from air within alveoli into the blood of pulmonary capillaries, and the diffusion of carbon dioxide in the opposite direction.
131
[23.6] What is internal respiration?
The exchange of oxygen and carbon dioxide between systemic capillaries and tissue cells.
132
[23.6] List the factors affecting internal respiration.
1. Partial pressure difference of gasses
2. Surface area available for gas exchange
3. Diffusion distance
4. Molecular weight and solubility of gases
133
[23.6] How does partial pressure difference of gasses affect internal respiration?
The partial pressure of oxygen must be higher in alveolar air than in pulmonary blood for it to diffuse, and likewise higher in the blood than tissue cells. When the difference is greater, diffusion is faster.
134
[23.6] How does surface area affect internal respiration?
The more contact air has with alveoli or alveolar air has with blood, the faster it can diffuse as a greater amount of oxygen can diffuse at the same time.
135
[23.6] How does diffusion distance affect internal respiration?
The lesser amount of tissue or cells the oxygen needs to diffuse through, the quicker diffusion occurs.
136
[23.6] How does solubility of molecules factor into internal respiration?
Carbon dioxide is about 24x more soluble than oxygen, meaning it is able to diffuse across membranes quicker than oxygen, leading to a better expulsion of carbon dioxide than intake of oxygen.
137
[23.7] How is oxygen transported in the blood?
By binding to hemoglobin, with traces amounts of oxygen dissolved in blood plasma.
138
[23.7] What is oxyhemoglobin?
Hemoglobin with an oxygen molecule bound to the iron portion.
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[23.7] What is fully saturated hemoglobin?
Hemoglobin that completely converted to oxyhemoglobin.
140
[23.7] What is partial saturation of hemoglobin?
Hemoglobin that has a mixture of hemoglobin and oxyhemoglobin.
141
[23.7] What is the percent saturation of hemoglobin?
The average saturation of hemoglobin within the body.
142
[23.7] What is affinity in relation to hemoglobin?
The intensity of attraction or bonding ability with which hemoglobin bonds oxygen.
143
[23.7] List the factors affecting affinity of hemoglobin for oxygen.
1. Acidity
2. Partial pressure of carbon dioxide
3. Temperature
4. BPG
144
[23.7] How does acidity affect affinity?
An increase in acidity decreases the affinity of hemoglobin for oxygen.
145
[23.7] What is the Bohr effect?
The change in affinity of hemoglobin for oxygen at any partial pressure based on pH, where an increase in acidity (lower pH) leads to a decrease affinity and a decrease in acidity (higher pH) increases affinity.
146
[23.7] How does partial pressure of carbon dioxide affect affinity?
Carbon dioxide is able to bind to hemoglobin and produces an effect similar to acidity. As carbon dioxide levels increase, hemoglobin affinity for oxygen decreases. Carbon dioxide entering blood is also converted into carbonic acid, which breaks down into acid and bicarbonate, increase acidity.
147
[23.7] How does temperature affect affinity?
An increase in temperature decreases affinity.
148
[23.7] What is BPG in relation to blood?
2,3-bisphosphoglycerate, produced in red blood cells during glycolysis.
149
[23.7] How does BPG affect affinity?
BPG is able to bind to sites on amino groups of hemoglobin, decreasing affinity for oxygen. Therefore, an increase in BPG is a decrease in affinity.
150
[23.7] How does fetal hemoglobin differ from adult hemoglobin?
Fetal hemoglobin has greater affinity for oxygen as it does not bind BPG as well
151
[23.7] List the ways carbon dioxide is transported in blood.
1. Dissolved carbon dioxide in blood plasma.
2. Carbamino compounds
3. Bicarbonate ions
152
[23.7] Describe how carbamino compounds transport carbon dioxide.
Carbon dioxide binds to amino groups of molecules (mainly hemoglobin) in blood forming carbamino compounds. Heavily reliant on partial pressure, leading to easy dissociation at pulmonary tissues.
153
[23.7] Describe how bicarbonate ions transport carbon dioxide.
Carbon dioxide diffusing into blood reacts with water to form carbonic acid, disassociating into hydrogen ions and bicarbonate. As bicarbonate reaches the lungs, this reaction is reversed and carbon dioxide is exhaled.
154
[23.7] What is the chloride shift?
An intake of chloride ions (-) into the RBCs as they expel HCO(-) to maintain electrical balance.
155
[23.7] What is the Haldane effect?
An effect in blood where low amounts of oxyhemoglobin, the higher the carbon dioxide carrying capacity.
156
[23.7] What characteristics contribute to the Haldane effect?
1. Hemoglobin binds to more carbon dioxide than oxyhemoglobin
2. Hemoglobin buffers hydrogen ions removing them from plasma and promoting conversion of carbon dioxide into carbonic acid.
157
[23.7] What is the respiratory center?
A formation of the medullary respiratory center and the pontine respiratory group.
158
[23.7] What makes up the medullary respiratory center?
The dorsal respiratory group and the ventral respiratory group.
159
[23.7] What is the pre-Botzinger complex?
A cluster of neurons believed to be important in generating the rhythm of breathing.
160
[23.7] What is the pontine respiratory area?
A group of nuclei in the pons active during inhalation and exhalation.
161
[23.7] What are chemoreceptors?
Sensory neurons sensitive to chemical stimuli.
162
[23.7] What are central chemoreceptors for breathing?
Chemoreceptors located in or near the medulla, found in the central nervous system.
163
[23.7] What are peripheral chemoreceptors for breathing?
Chemoreceptors located in the aortic bodies such as arch of aorta, and in carotid bodies of the left and right common carotid arteries.
164
[23.7] What is hypercapnia?
Higher than normal levels of carbon dioxide, typically above 40 mmHg partial pressure.
165
[23.7] What is hyperventilation?
A rapid and deep pattern of breathing in reaction to imbalance of gasses, typically in response to hypercapnia and meant to restore normal levels of oxygen and carbon dioxide.
166
[23.7] What is hypocapnia?
Lower than normal levels of carbon dioxide, below 40 mmHg partial pressure.
167
[23.7] How does proprioception stimulate breathing?
Nerve impulses generated by proprioceptors stimulate the dorsal respiratory group of the medulla to increase breathing rate.
168
[23.7] What's the inflation reflex?
Stimulation of the dorsal respiratory group to be inhibited, relaxing the diaphragm and external intercostals. Stimuli is generated from baroreceptors within bronchi and bronchioles when pressure or stretch increases too much.
169
[23.7] List the main stimuli that affect breathing rate and depth.
1. Voluntary hyperventilation
2. Increase of arterial partial pressure of carbon dioxide
3. Decrease of arterial partial pressure of oxygen
4. Activity of proprioceptors
5. Increase in temperature
6. Pain
7. Decrease in blood pressure
8. Stretching of anal sphincter
9. Limbic system stimulation.
