respiration Flashcards
(260 cards)
1
Q
Describe the condition characterized by reversible bronchospasm and chronic inflammation of airway passages.
A
Asthma is a condition characterized by reversible bronchospasm and chronic inflammation of airway passages.
2
Q
How has the incidence of asthma changed in recent years?
A
The incidence of asthma has been steadily increasing in recent years.
3
Q
Define the genetic aspect of asthma development.
A
There appears to be a definite genetic predisposition to the development of asthma.
4
Q
key component of asthma
A
A key component of asthma appears to be airway ‘hyper reactivity’ in affected individuals.
5
Q
List some common triggers that can induce bronchospasm in asthma patients.
A
Common triggers include allergens like pollen, pet dander, fungi, dust mites, cold air, pollutants, cigarette smoke, strong emotions, exercise, and respiratory tract infections.
6
Q
Describe the role of IgE in asthma.
A
Individuals with asthma produce large amounts of the antibody IgE that attach to mast cells, which can lead to the release of inflammatory mediators when exposed to triggers.
7
Q
What happens during the early phase of an asthma attack?
A
The early phase of asthma is characterized by marked constriction of bronchial airways (bronchospasm), edema of the airways, and production of excess mucus.
8
Q
Identify the inflammatory mediators involved in the early phase of asthma.
A
The early phase of asthma involves the increased release of inflammatory mediators such as histamine, prostaglandins, and bradykinin.
9
Q
What characterizes the late phase of asthma?
A
The late phase of asthma is characterized by an inflammatory response that occurs several hours after the initial onset of symptoms.
10
Q
Which white blood cells are primarily involved in the late phase of asthma?
A
Eosinophils are the primary mediators of inflammation during the late phase of the asthmatic response.
11
Q
How do neutrophils and lymphocytes contribute to asthma in the late phase
A
Neutrophils and lymphocytes infiltrate the airway tissues, contributing to the overall inflammatory response in the late phase of asthma.
12
Q
Describe the manifestations of bronchial asthma.
A
Coughing, wheezing, difficulty breathing, rapid shallow breathing, increased respiratory rate, excess mucus production, and significant anxiety.
13
Q
Define severe acute asthma.
A
A life-threatening condition characterized by prolonged bronchospasm that is often unresponsive to drug therapy.
14
Q
How can pneumothorax occur in asthma patients?
A
Pneumothorax can result from increased lung pressure due to extreme difficulty in expiration during a prolonged asthma attack.
15
Q
What are the potential complications of asthma?
A
Severe acute asthma, pneumothorax, and respiratory failure, which may involve marked hypoxemia and acidosis.
16
Q
Explain chronic obstructive pulmonary disease (COPD).
A
COPD is a group of lung conditions that cause breathing difficulties, including emphysema and chronic bronchitis.
17
Q
Describe emphysema and its characteristics.
A
Emphysema is characterized by the destruction and permanent enlargement of terminal bronchioles and alveolar air sacs, leading to loss of lung tissue elasticity and decreased surface area for gas exchange.
18
Q
What role does tissue elasticity play in the lungs?
A
Tissue elasticity helps keep airways open, acting like a spring, and prevents them from collapsing during expiration.
19
Q
How does chronic cigarette smoking affect the lungs in emphysema patients?
A
Chronic cigarette smoking causes inflammation of the alveolar airways, leading to destruction of elastic walls of the alveoli by leukocytes and excess release of protease enzymes.
20
Q
What is the significance of α-1-antitrypsin in emphysema?
A
α-1-antitrypsin is a protective enzyme that is often lacking in chronic cigarette smokers, contributing to lung damage.
21
Q
Identify the two main conditions included in COPD.
A
Emphysema and chronic bronchitis.
22
Q
Describe the role of α-1-antitrypsin in lung tissue.
A
α-1-antitrypsin inactivates destructive protease enzymes, such as trypsin, in lung tissue.
22
Q
What is chronic bronchitis?
A
Chronic bronchitis is the long-term inflammation of the bronchial tubes, which leads to a persistent cough.
23
Q
Define emphysema and its main cause.
A
Emphysema is an obstructive respiratory disorder mainly caused by the loss of alveolar elasticity and a decrease in the overall surface area for gas exchange within the lungs.
24
How does tachypnea manifest in emphysema patients?
Tachypnea, or increased respiratory rate, occurs as a compensatory mechanism to maintain arterial blood gases.
25
What are the late-stage symptoms of emphysema?
Hypoxia or cyanosis is typically not seen until the end stages of the disease.
26
Explain the term 'barrel chest' in relation to emphysema.
Barrel chest refers to the physical change in the chest shape due to prolonged expiration in emphysema patients.
27
What are the possible long-term consequences of emphysema?
Possible long-term consequences of emphysema include respiratory failure.
28
Describe pneumothorax and its effect on lung expansion.
Pneumothorax is the entry of air into the pleural cavity, which disrupts the negative pressure necessary for normal lung expansion, leading to lung collapse.
29
How does a closed or spontaneous pneumothorax occur?
A closed or spontaneous pneumothorax occurs when air leaks from the lungs into the pleural cavity, often due to lung cancer, rupture, or pulmonary disease.
30
What is a pen or communicating pneumothorax?
A pen or communicating pneumothorax involves a traumatic chest wound where air enters the pleural cavity from the atmosphere, causing lung collapse.
31
Define tension pneumothorax.
Tension pneumothorax is a condition characterized by a one-way movement of air into the pleural cavity, preventing air from escaping and leading to increased pressure.
32
How does the presence of air in the pleural cavity affect lung function?
The presence of air in the pleural cavity disrupts the negative pressure needed for lung expansion, resulting in lung collapse.
33
Describe the condition that may involve a hole or wound to the pleural cavity.
It allows air to enter the pleural cavity, leading to lung collapse.
34
How does expiration affect a hole in the pleural cavity?
Upon expiration, the hole or opening closes, preventing air from moving back out of the pleural cavity.
34
Define pneumothorax and its potential consequences.
Pneumothorax is a life-threatening condition where pressure in the pleural cavity increases, potentially compressing the lung and large blood vessels.
35
List the manifestations of pneumothorax.
Tachypnea, dyspnea, chest pain, and possible compression of thoracic blood vessels and heart.
36
What is the treatment for pneumothorax?
Treatment includes removal of air from the pleural cavity with a needle or chest tube and repair of trauma to close the opening.
37
Identify the symptoms associated with pneumothorax.
Symptoms include rapid breathing (tachypnea), difficulty breathing (dyspnea), and chest pain.
37
Explain the significance of tension pneumothorax.
Tension pneumothorax can lead to severe compression of thoracic blood vessels and the heart, making it a critical condition.
38
How can pneumothorax be life-threatening?
It can lead to increased pressure in the pleural cavity, resulting in lung compression and potential cardiovascular complications.
39
What role does a chest tube play in the treatment of pneumothorax?
A chest tube is used to remove air from the pleural cavity to allow the lung to re-expand.
40
Describe the process of repairing a pneumothorax.
Repair involves closing the opening in the pleural cavity to prevent further air entry.
41
Describe the general symptoms of respiratory diseases.
General symptoms include hypoxia, hypoxemia, hypercapnia, hypocapnia, dyspnea, tachypnea, cyanosis, and hemoptysis.
42
Define hypoxia and its significance in respiratory diseases.
Hypoxia refers to decreased levels of oxygen in the tissues, which can lead to serious health issues if not addressed.
43
How do obstructive pulmonary disorders affect airflow?
Obstructive pulmonary disorders, such as asthma and emphysema, obstruct airflow into and out of the lungs, making breathing difficult.
44
What are restrictive pulmonary disorders and give examples.
Restrictive pulmonary disorders limit normal expansion of the lungs; examples include pneumothorax, atelectasis, respiratory distress syndrome, and cystic fibrosis.
45
Identify common infections of the respiratory system.
Common infections include influenza and pneumonia, which can affect either the upper or lower respiratory tract.
46
Explain the difference between hypoxemia and hypoxia.
Hypoxemia is the decreased levels of oxygen in arterial blood, while hypoxia refers to decreased oxygen levels in the tissues.
47
What is hemoptysis and what does it indicate?
Hemoptysis is the presence of blood in the sputum, indicating possible respiratory issues or infections.
48
Describe the role of inhaled particles in respiratory diseases.
Inhaled particles can alter pulmonary function and contribute to respiratory diseases, including cancers.
49
How does dyspnea manifest in respiratory disorders?
Dyspnea manifests as difficulty breathing, which can be a symptom of various respiratory conditions.
50
What is tachypnea and when might it occur?
Tachypnea is a rapid rate of breathing that may occur in response to respiratory distress or other health issues.
51
Define hypercapnia and its potential effects on the body.
Hypercapnia is the increased levels of CO2 in the blood, which can lead to respiratory acidosis and other complications.
52
What are the two main types of respiratory tract infections?
The two main types of respiratory tract infections are those affecting the upper respiratory tract and those affecting the lower respiratory tract.
53
List some obstructive pulmonary disorders.
Obstructive pulmonary disorders include asthma, bronchitis, and emphysema.
54
What is cyanosis and what does it indicate about oxygenation?
Cyanosis is a bluish discoloration of skin and mucous membranes due to poor oxygenation of the blood.
55
How can respiratory infections be categorized?
Respiratory infections can be categorized based on their location: upper respiratory tract, lower respiratory tract, or both.
56
Describe the primary causes of upper respiratory tract infections.
The majority of upper respiratory tract infections are caused by viruses, particularly rhinovirus and parainfluenza virus.
57
Define the common cold and its primary viral pathogens.
The common cold is a viral infection primarily caused by rhinovirus, parainfluenza virus, adenovirus, and coronavirus.
58
How do viruses responsible for the common cold enter the body?
These viruses gain entry to the body through the nasal mucosa and the surfaces of the eye.
59
Explain how the common cold spreads from person to person.
The common cold spreads via respiratory secretions.
60
List the manifestations of the common cold.
Manifestations include rhinitis, sinusitis, pharyngitis, headache, and nasal discharge and congestion.
61
What is rhinitis?
Rhinitis is the inflammation of the nasal mucosa.
62
What is sinusitis?
Sinusitis is the inflammation of the sinus mucosa.
63
What is pharyngitis?
Pharyngitis is the inflammation of the pharynx and throat.
64
Identify the three distinct forms of influenza virus.
The three forms of influenza virus are A, B, and C, with type A being the most common and causing the most serious illness.
65
Describe influenza and its impact on the respiratory tract.
Influenza is a viral infection that can affect both the upper and lower respiratory tract.
66
How does the influenza virus mutate and why is it significant?
The influenza virus has a high tendency for genetic mutation, leading to the constant emergence of new variants, which can result in serious pandemics.
67
What is the frequency of serious influenza pandemics?
Serious pandemics of influenza occur approximately every 8 to 10 years.
68
What were the symptoms of the H1N1 influenza pandemic in 2009?
Symptoms included headache, fever, chills, muscle aches, nasal discharge, unproductive cough, and sore throat.
69
How does influenza infection affect the respiratory epithelium?
Influenza infection can cause marked inflammation of the respiratory epithelium, leading to acute tissue damage and a loss of ciliated cells.
70
What role do ciliated cells play in the respiratory system?
Ciliated cells help protect the respiratory passages from other organisms.
71
Describe the potential complications of influenza infection.
Influenza infection may lead to co-infection of the respiratory passages with bacteria and can also cause viral pneumonia by infecting lung tissues.
72
How is influenza typically treated?
Treatment of influenza includes bed rest, fluids, warmth, antiviral drugs, and vaccination.
73
Define the purpose of the influenza vaccine.
The influenza vaccine provides protection against certain A and B influenza strains expected to be prevalent in a given year and must be updated and administered yearly.
74
Identify the groups for whom the influenza vaccine is particularly indicated.
The influenza vaccine is particularly indicated for elderly people, individuals weakened by other diseases, and health-care workers.
75
Explain the condition of pneumonia.
Pneumonia involves inflammation of lower lung structures such as the alveoli and can be caused by bacteria or viruses.
76
How has the prevalence and severity of pneumonia changed in recent years?
The prevalence and severity of pneumonia have increased due to antibiotic resistance.
77
Classify pneumonia based on the setting of infection.
Pneumonia can be classified as community-acquired pneumonia (CAP) or hospital-acquired pneumonia (HAP), which includes ventilator-associated pneumonia (VAP) and healthcare-associated pneumonia (HCAP).
78
List individuals most at risk for pneumonia.
Individuals most at risk for pneumonia include the elderly, those with viral infections, chronically ill patients, AIDS or immunosuppressed patients, smokers, and patients with chronic respiratory diseases.
79
Identify typical pathogens that cause pneumonia.
Typical pathogens causing pneumonia include Streptococcus pneumoniae, Hemophilus influenzae, Mycobacterium catarrhalis, and Klebsiella pneumoniae.
80
Name some atypical pathogens associated with pneumonia.
Atypical pathogens associated with pneumonia include Chlamydia pneumoniae, Legionella pneumophila, and Mycoplasma pneumoniae.
81
What are some less common pathogens that can cause pneumonia?
Less common pathogens that can cause pneumonia include various viruses and fungi.
82
Describe typical pneumonia and its manifestations.
Typical pneumonia is usually bacterial in origin, with organisms replicating in the spaces of the alveoli. Manifestations include inflammation and fluid accumulation in the alveoli, white cell exudation visible on chest radiographs, high fever, chest pain, chills, malaise, and some degree of hypoxemia.
83
How does atypical pneumonia differ from typical pneumonia?
Atypical pneumonia involves organisms replicating in the spaces around the alveoli, leading to milder symptoms compared to typical pneumonia. It is characterized by a lack of white cell infiltration and fluid accumulation in the alveoli.
84
Define opportunistic organisms in the context of pneumonia.
Opportunistic organisms are those not commonly associated with respiratory illness in healthy individuals but can cause severe respiratory infections and pneumonia in patients with HIV or those who are immunocompromised due to immune suppressive therapy.
85
List some organisms that can cause opportunistic pneumonia in immunocompromised patients.
Organisms that can cause opportunistic pneumonia in immunocompromised patients include mycobacteria, fungi such as Histoplasma, and protozoa like Pneumocystis carinii.
86
What is required for the treatment of opportunistic pneumonia caused by certain organisms?
The treatment of opportunistic pneumonia caused by specific organisms requires targeted drug therapy, and in the case of protozoa and fungi, these organisms can be very difficult to eliminate.
87
Explain the role of inflammation in typical pneumonia.
In typical pneumonia, inflammation occurs in the alveoli, leading to fluid accumulation and contributing to symptoms such as high fever and chest pain.
88
Identify the symptoms associated with typical pneumonia.
Symptoms of typical pneumonia include high fever, chest pain, chills, malaise, and some degree of hypoxemia.
89
What is the significance of white cell exudation in pneumonia diagnosis?
White cell exudation in pneumonia is significant as it can be seen on chest radiographs and indicates an inflammatory response to infection.
90
How do the symptoms of atypical pneumonia compare to those of typical pneumonia?
The symptoms of atypical pneumonia are milder than those of typical pneumonia, reflecting a less severe inflammatory response.
91
Describe the replication location of organisms in typical pneumonia.
In typical pneumonia, organisms replicate in the spaces of the alveoli.
92
Describe the replication location of organisms in atypical pneumonia.
In atypical pneumonia, organisms replicate in the spaces around the alveoli.
93
Describe the general mechanism of gas exchanges in the body.
Gas exchanges in the body involve the transport of oxygen from the atmosphere to the cells and the expulsion of carbon dioxide from the cells to the atmosphere, primarily occurring in the lungs and tissues.
94
Define external respiration.
External respiration is the exchange of gases between the air in the alveoli and the blood in the pulmonary capillaries.
95
Explain the importance of partial pressure in gas exchange.
Partial pressure is crucial in gas exchange as it determines the direction of gas diffusion, with gases moving from areas of higher partial pressure to areas of lower partial pressure.
96
How does the body maintain homeostasis regarding oxygen and carbon dioxide levels?
The body maintains homeostasis by obtaining oxygen from the atmosphere and expelling carbon dioxide, ensuring that the cells receive the oxygen they need while removing waste gases.
97
What is the average amount of oxygen consumed by the body at rest per minute?
The body consumes approximately 250 mL of oxygen per minute when at rest.
98
Describe the process of internal respiration.
Internal respiration is the exchange of gases between the blood in the systemic capillaries and the tissue fluid (cells) of the body.
99
How much air does an average adult male inhale per minute, and how much reaches the alveoli?
An average adult male inhales 6000 mL of air per minute, with approximately 4200 mL reaching the alveoli.
100
What is the Haldane effect?
The Haldane effect refers to the increased ability of deoxygenated blood to carry carbon dioxide, enhancing the efficiency of gas exchange.
101
What is the Bohr effect?
The Bohr effect describes how increased carbon dioxide concentration and decreased pH in the blood lead to a reduction in hemoglobin's affinity for oxygen, facilitating oxygen release to tissues.
102
How much oxygen does the body consume in a day?
The body consumes approximately 360,000 mL of oxygen per day, which is about 100 gallons.
103
What happens to the blood in the pulmonary capillaries during external respiration?
During external respiration, the blood in the pulmonary capillaries, which has a low PO2 and high PCO2, gains oxygen and loses carbon dioxide, resulting in higher PO2 and lower PCO2.
104
Explain the role of circulation in gas exchange.
Circulation plays a vital role in gas exchange by transporting oxygen to the cells and carrying carbon dioxide away from the cells to the lungs for expulsion.
105
What is the significance of the alveoli in gas exchange?
The alveoli are significant in gas exchange as they provide a large surface area for the diffusion of oxygen into the blood and carbon dioxide out of the blood.
106
How does the concentration of gases affect their diffusion in the body?
Gases diffuse from areas of greater concentration to areas of lesser concentration, which is influenced by their partial pressures in different sites within the body.
107
What is the composition of air that reaches the alveoli?
Approximately 882 mL of the air that reaches the alveoli is oxygen, which constitutes about 21% of the inhaled air.
108
What is the relationship between oxygen saturation and partial pressure?
Oxygen saturation is influenced by the partial pressure of oxygen; higher partial pressures generally lead to higher oxygen saturation in the blood.
109
How does oxygen transport in the blood occur?
Oxygen transport in the blood occurs through a reversible mechanism where oxygen enters the blood in the lungs and is released in tissues, primarily facilitated by hemoglobin.
110
Define oxyhemoglobin and deoxyhemoglobin.
Oxyhemoglobin is the complex formed when hemoglobin binds with oxygen, while deoxyhemoglobin refers to hemoglobin without any bound oxygen.
111
Explain the significance of hemoglobin's structure in oxygen transport.
Hemoglobin consists of four subunits, each containing a heme group capable of binding one oxygen molecule, allowing it to carry a total of four oxygen molecules.
112
How does the partial pressure of oxygen (PO2) affect hemoglobin's ability to bind oxygen?
High PO2 facilitates the binding of oxygen to hemoglobin, while low PO2 promotes the release of oxygen from hemoglobin.
113
What is the relationship between dissolved oxygen and oxygen bound to hemoglobin?
Dissolved oxygen contributes to the partial pressure of oxygen (PO2) in blood, while oxygen bound to hemoglobin is in equilibrium with dissolved oxygen, affecting the amount of oxygen that can be carried.
114
Describe the process of oxygen binding and release by hemoglobin.
Oxygen binds to hemoglobin in the lungs where PO2 is high, and it is released in respiring tissues where PO2 is low, allowing for efficient oxygen transport.
115
What is the typical oxygen content in arterial blood?
Every liter of arterial blood contains about 200 mL of oxygen, with approximately 3 mL dissolved in plasma and 197 mL bound to hemoglobin.
116
How does hemoglobin ensure efficient oxygen transport?
Hemoglobin binds oxygen tightly enough to pick up large quantities in the lungs but not so tightly that it cannot release it in respiring tissues.
117
What happens to blood as it returns to the heart after internal respiration?
Blood returning to the heart has a low PO2 and a high PCO2, and it is pumped by the right ventricle to the lungs for external respiration.
118
What is the significance of the equilibrium between bound and dissolved oxygen?
The equilibrium between bound and dissolved oxygen allows hemoglobin to effectively transport oxygen while maintaining the necessary partial pressure for oxygen release.
119
How many oxygen molecules can one hemoglobin molecule carry?
One hemoglobin molecule can carry a total of four oxygen molecules due to its four heme groups.
120
What is the effect of high and low PO2 on hemoglobin?
High PO2 promotes the binding of oxygen to hemoglobin, while low PO2 facilitates the release of oxygen from hemoglobin.
121
Describe the saturation of oxygen in arterial blood.
In arterial blood, the partial pressure of oxygen is approximately 100 mm Hg, resulting in hemoglobin being about 98% saturated with oxygen.
122
Describe the saturation level of hemoglobin in mixed venous blood.
In mixed venous blood, the partial pressure of oxygen is 40 mm Hg, and hemoglobin is 75% saturated, meaning three of every four binding sites are occupied by oxygen.
123
How does the binding of one oxygen molecule affect hemoglobin's affinity for additional oxygen molecules?
The binding of one oxygen molecule to hemoglobin increases the affinity of the hemoglobin molecule for another oxygen molecule.
124
Define the leftward shift in the hemoglobin oxygen dissociation curve.
A leftward shift indicates that oxygen is loaded more easily onto hemoglobin, often due to increased affinity.
125
How does temperature influence hemoglobin's affinity for oxygen?
As temperature increases due to tissue metabolism, the affinity of hemoglobin for oxygen decreases, resulting in more oxygen being unloaded in active tissues.
125
What does a rightward shift in the hemoglobin oxygen dissociation curve indicate?
A rightward shift indicates that oxygen is unloaded more easily from hemoglobin, making it more available to the tissue.
126
Explain the Bohr effect in relation to pH and hemoglobin.
The Bohr effect describes how an increase in hydrogen ion concentration (a decrease in pH) causes some oxygen to dissociate from hemoglobin, decreasing its affinity for oxygen and facilitating oxygen unloading.
127
What role does carbon dioxide play in the affinity of hemoglobin for oxygen?
Carbon dioxide reacts with hemoglobin to form carbaminohemoglobin, and an increase in PCO2 decreases hemoglobin's affinity for oxygen, promoting oxygen unloading.
128
Describe the effect of 2,3-bisphosphoglycerate (2,3-BPG) on hemoglobin's affinity for oxygen.
2,3-BPG decreases the affinity of hemoglobin for oxygen, especially when oxyhemoglobin levels are low, which occurs when oxygen supply is limited.
129
How does the structure of hemoglobin change with temperature variations?
Temperature affects the structure of hemoglobin, altering its affinity for oxygen; higher temperatures decrease affinity, while lower temperatures increase it.
130
What happens to hemoglobin's affinity for oxygen as blood travels to the lungs?
As blood travels to the lungs and temperature decreases, hemoglobin's affinity for oxygen increases, promoting oxygen loading.
131
Describe the effect that enhances oxygen unloading in respiring tissues.
The effect that enhances oxygen unloading in respiring tissues is influenced by factors such as anemia and high altitudes, which increase the production of 2,3-BPG.
132
Define the primary forms of carbon dioxide transport in the blood.
Carbon dioxide is transported in the blood in three primary forms: 5-6% is dissolved, 5-8% is bound to hemoglobin as carbaminohemoglobin, and 86-90% is dissolved as bicarbonate ions (HCO3-).
133
How is bicarbonate formed in erythrocytes?
Bicarbonate is formed from carbon dioxide within erythrocytes in systemic capillaries, facilitated by the enzyme carbonic anhydrase.
134
Explain the role of carbonic anhydrase in carbon dioxide transport.
Carbonic anhydrase catalyzes the reversible reaction that converts carbon dioxide and water into carbonic acid (H2CO3), which then dissociates into hydrogen ions and bicarbonate ions.
135
What happens to blood pH when carbon dioxide levels increase?
An increase in blood carbon dioxide levels causes a decrease in blood pH.
136
How much carbon dioxide do respiring cells produce at rest?
Respiring cells produce carbon dioxide at a rate of approximately 200 mL/min at rest.
137
Describe the process of carbon dioxide diffusion from respiring cells to the plasma.
Carbon dioxide produced in respiring cells diffuses into interstitial fluid and then into the plasma based on its partial pressure gradient.
138
How does an increase in PO2 affect carbon dioxide transport bound to hemoglobin?
An increase in PO2 decreases the amount of carbon dioxide that can be transported bound to hemoglobin because hemoglobin is carrying more oxygen.
139
What occurs in respiring tissues regarding the Haldane effect?
In respiring tissues, where PO2 is low and PCO2 is high, the Haldane effect promotes the loading of carbon dioxide onto hemoglobin.
140
Explain the interaction of the Haldane effect with the Bohr and carbamino effects in the lungs.
In the lungs, where PO2 is high and PCO2 is low, the Haldane effect promotes the unloading of carbon dioxide, while the Bohr effect and the carbamino effect promote oxygen loading.
141
How does the respiratory rate change with activity levels?
The respiratory rate increases when active and decreases when less active or sleeping.
142
What is the nature of control over respiratory muscles during sleep?
Although the respiratory muscles are voluntary, they cannot be consciously controlled when sleeping.
143
Describe the role of the rhythmicity center in the medulla.
The rhythmicity center of the medulla controls automatic breathing through interacting neurons that activate during inspiration (I neurons) or expiration (E neurons). I neurons stimulate respiratory muscles for inspiration, while E neurons inhibit I neurons to facilitate expiration.
144
How do the apneustic and pneumotaxic centers influence respiration?
The apneustic center, located in the pons, stimulates I neurons to promote inspiration, while the pneumotaxic center inhibits the apneustic center and thus inhibits inspiration.
145
Define chemical regulation in the context of respiration.
Chemical regulation refers to the influence of blood pH and levels of oxygen and carbon dioxide on breathing. It involves chemoreceptors that detect changes in these blood gases and pH.
146
Explain the response of the body to low oxygen levels.
Low oxygen levels (hypoxia) signal the brain to increase the respiratory rate, leading to enhanced oxygen intake.
147
What happens in the body when carbon dioxide levels are high?
High carbon dioxide levels reduce blood pH, leading to the formation of carbonic acid and increased H+ ions, which signal the brain to increase respiration and enhance exhalation.
148
Identify the locations of chemoreceptors involved in respiration control.
Chemoreceptors that detect changes in blood gases and pH are located in the carotid and aortic bodies, as well as in the medulla.
149
How do I neurons and E neurons interact during the breathing process?
I neurons stimulate respiratory muscles for inspiration, while E neurons inhibit I neurons to facilitate expiration, creating a balance in the breathing cycle.
150
Discuss the significance of blood pH in respiratory control.
Blood pH is significant in respiratory control as a decrease in pH (due to high CO2 levels) triggers an increase in respiration to expel more carbon dioxide and restore pH balance.
151
What is the effect of increased respiratory rate on oxygen levels?
An increased respiratory rate enhances oxygen intake, helping to counteract low oxygen levels in the body.
152
Summarize the main functions of the medulla in respiration.
The medulla's main functions in respiration include controlling automatic breathing through the rhythmicity center, regulating the balance between inspiration and expiration, and responding to chemical changes in blood gases.
153
Describe forced breathing.
Forced breathing is an active mode of breathing that utilizes additional muscles to rapidly expand and contract the thoracic cavity volume, commonly occurring during exercise.
154
Define airway resistance.
Airway resistance refers to the resistance of the entire system of airways in the respiratory tract.
155
How does airway radius affect airway resistance?
As the airway radius decreases, airway resistance increases.
156
Explain the relationship between asthma and airway resistance.
Asthma is associated with an increase in airway resistance due to spastic contractions of the smooth muscle in bronchioles, along with increased mucus secretion and inflammation of the bronchioles.
157
What role does histamine play in airway resistance?
Histamine, released during allergic reactions, causes contraction of the smooth muscle leading to bronchoconstriction and stimulates mucus secretion, increasing resistance to airflow.
158
How do carbon dioxide levels influence bronchiole behavior?
When carbon dioxide levels are high, bronchioles dilate; when carbon dioxide levels are low, bronchioles constrict.
159
List the symptoms associated with asthma.
Symptoms of asthma include coughing, dyspnea (labored breathing), and wheezing.
160
Do spastic contractions of smooth muscle affect breathing?
Yes, spastic contractions of smooth muscle in bronchioles increase airway resistance, making breathing more difficult.
161
What happens to mucus secretion during an allergic reaction?
During an allergic reaction, histamine stimulates increased mucus secretion, which contributes to airway resistance.
162
Describe the main causes of asthma.
Asthma is often caused by hypersensitivity to allergens such as fungi, dust mites, or animal dander, and can also be induced by stress, exercise, certain foods, or breathing cold air.
163
How does asthma affect lung function?
In asthma, a person’s forced expiratory volume declines due to increased airway resistance.
164
Define tidal volume (TV).
Tidal volume (TV) is the normal volume of air inspired or expired during quiet breathing, typically around 500 ml.
165
What is inspiratory reserve volume (IRV)?
Inspiratory Reserve Volume (IRV) is the extra volume of air inhaled after tidal volume by maximum inspiratory effort, approximately 3000 ml in an adult male.
166
Explain expiratory reserve volume (ERV).
Expiratory Reserve Volume (ERV) is the extra volume of air that can be exhaled after tidal volume by maximum expiratory efforts, about 1100 ml in a normal adult male.
167
What is residual volume (RV)?
Residual Volume (RV) is the volume of air left in the lungs after forceful inspiration or complete expiration, approximately 1200 ml in an adult male.
168
How do lung volumes and capacities relate to each other?
Lung volumes are directly measured, while lung capacities are inferred from these lung volumes.
169
Describe dead space volume in the respiratory system.
Dead space volume refers to the air that enters the respiratory tract and remains within the conducting zone passageways, which never reaches the alveoli.
170
What is the purpose of a lung volume test?
A lung volume test measures the total amount of air in the lungs and how much air remains after maximal exhalation.
171
List the four types of lung volumes.
The four types of lung volumes are Tidal Volume (TV), Inspiratory Reserve Volume (IRV), Expiratory Reserve Volume (ERV), and Residual Volume (RV).
172
How is total lung capacity determined?
Total lung capacity is determined by the sum of the four lung volumes: Tidal Volume, Inspiratory Reserve Volume, Expiratory Reserve Volume, and Residual Volume.
173
Describe the function of a spirometer.
A spirometer is used to measure the amount of air inhaled and exhaled with each breath.
174
How can a spirometer assist in diagnosing lung conditions?
A spirometer can help diagnose lung conditions by measuring airflow and lung capacity, indicating whether conditions are restrictive (like pulmonary fibrosis) or obstructive (like asthma).
175
Define restrictive lung conditions and provide an example.
Restrictive lung conditions are characterized by reduced lung volume and difficulty fully expanding the lungs. An example is pulmonary fibrosis.
176
Define obstructive lung conditions and provide an example.
Obstructive lung conditions are characterized by difficulty exhaling air due to airway obstruction. An example is asthma.
177
What type of lung condition is asthma classified as?
Asthma is classified as an obstructive lung condition.
178
What is the significance of measuring lung volumes?
Measuring lung volumes is significant for diagnosing and monitoring lung diseases and understanding respiratory function.
179
Describe the mechanism of breathing during inspiration.
Inspiration occurs when the pressure in the alveoli is less than the pressure in the atmosphere, creating a pressure gradient that allows air to move into the alveoli.
180
Explain the role of pulmonary pressures in ventilation.
Air flow into or out of the lungs is driven by pressure gradients, with ventilation occurring due to the differences in pressure between the alveoli and the outside air.
181
Define Boyle's law in the context of breathing.
Boyle's law states that the pressure of a gas is inversely proportional to its volume, which is fundamental in understanding how changes in lung volume during breathing affect pressure and airflow.
182
How does expiration occur in the respiratory system?
Expiration occurs when the pressure in the alveoli exceeds the pressure in the atmosphere, creating a pressure gradient that allows air to leave the alveoli.
183
What is atmospheric pressure?
Atmospheric pressure is the pressure exerted by the weight of the outside air.
184
Describe the relationship between airway resistance and forced breathing.
Airway resistance affects the ease with which air can flow into and out of the lungs, and during forced breathing, the body must overcome this resistance to achieve adequate ventilation.
185
Explain how air moves in relation to pressure gradients during breathing.
Air moves down a pressure gradient, from areas of high pressure to areas of low pressure, facilitating the processes of inspiration and expiration.
186
What happens to alveolar pressure during inspiration?
During inspiration, alveolar pressure decreases, becoming lower than atmospheric pressure, which allows air to flow into the lungs.
187
What happens to alveolar pressure during expiration?
During expiration, alveolar pressure increases, exceeding atmospheric pressure, which causes air to flow out of the lungs.
188
Describe the relationship between atmospheric pressure and altitude.
Atmospheric pressure decreases at altitudes higher than sea level.
189
Define intra-alveolar pressure and its significance in ventilation.
Intra-alveolar pressure (Palv) is the pressure of air within the alveoli, which varies during ventilation and creates the pressure gradient that drives air movement.
190
How does intra-alveolar pressure change during inspiration?
During inspiration, atmospheric pressure exceeds intra-alveolar pressure, causing air to flow into the lungs.
191
What is the functional residual capacity (FRC)?
The functional residual capacity (FRC) is the volume of air in the lungs between breaths.
192
Explain the concept of intrapleural pressure.
Intrapleural pressure (Pip) is the pressure inside the pleural space, which contains intrapleural fluid and is typically −4 mm Hg at rest.
193
Define transpulmonary pressure and its role in lung function.
Transpulmonary pressure is the difference between intra-alveolar pressure and intrapleural pressure, influencing lung expansion and distending pressure.
194
How does an increase in transpulmonary pressure affect the lungs?
An increase in transpulmonary pressure creates a larger distending pressure across the lungs, leading to lung expansion.
195
What happens to intra-alveolar pressure at rest?
At rest, intra-alveolar pressure is equal to atmospheric pressure, which is 0 mm Hg.
196
Describe the pressure gradient that drives ventilation.
The pressure gradient that drives ventilation is the difference between intra-alveolar pressure and atmospheric pressure.
197
What is the significance of the intrapleural space in respiration?
The intrapleural space contains fluid that helps maintain negative pressure, which is essential for lung inflation.
198
Describe the process of breathing.
Breathing consists of two main phases: inspiration (breathing in) and expiration (breathing out).
199
Breathing consists of two main phases: inspiration (breathing in) and expiration (breathing out).
Inspiration is the phase of ventilation where air enters the lungs, initiated by the contraction of the diaphragm and intercostal muscles.
200
How does the diaphragm contribute to inspiration?
The diaphragm contracts and flattens, increasing the superior/inferior dimension of the thoracic cavity, which helps draw air into the lungs.
201
What role do the intercostal muscles play during inspiration?
The external intercostal muscles elevate the ribs and sternum, increasing the anterior/posterior dimension of the thoracic cavity.
202
Explain Boyle's law in relation to breathing.
Boyle's law states that an increase in the volume of the thoracic cavity during inspiration leads to a decrease in pressure, causing air to flow into the lungs.
203
Describe the mechanism of passive expiration.
Passive expiration is the phase of ventilation where air is expelled from the lungs without active muscle contraction, typically occurring after inspiration.
204
What happens to the thoracic cavity during inspiration?
During inspiration, the volume of the thoracic cavity increases due to the contraction of the diaphragm and intercostal muscles.
205
How does increased volume in the thoracic cavity affect air pressure?
Increased volume in the thoracic cavity leads to decreased pressure, allowing air to flow into the lungs.
206
Identify the two main muscles involved in breathing.
The two main muscles involved in breathing are the diaphragm and the intercostal muscles.
207
Describe the role of the diaphragm in the process of expiration.
During expiration, the diaphragm muscles relax, allowing the diaphragm to curve upwards, which reduces the superior/inferior dimension of the thoracic cavity.
207
What is the significance of breathing for the body?
Breathing is vital for life as it provides oxygen to tissues and removes carbon dioxide from the body.
208
Define the process of expiration in terms of lung volume.
Expiration is the phase of ventilation where air is expelled from the lungs, initiated by the relaxation of inspiratory muscles, leading to a decrease in the volume of the thoracic cavity.
209
How do the external intercostal muscles contribute to expiration?
The external intercostal muscles relax to depress the ribs and sternum, which reduces the anterior/posterior dimension of the thoracic cavity.
210
What happens to lung tissue during expiration?
The elastic recoil of the previously expanded lung tissue allows the lungs to return to their original size during expiration.
211
Explain the difference between inspiration and expiration.
Inspiration is the phase where air enters the lungs, initiated by the contraction of inspiratory muscles, while expiration is the phase where air is expelled from the lungs, initiated by the relaxation of those muscles.
212
What initiates the process of inspiration?
Inspiration is initiated by the contraction of the inspiratory muscles, primarily the diaphragm and external intercostal muscles.
213
How does the thoracic cavity change during expiration?
During expiration, the thoracic cavity's volume decreases due to the relaxation of the diaphragm and external intercostal muscles.
214
Define external respiration.
External respiration refers to the exchange of oxygen and carbon dioxide between the atmosphere and body tissues, involving both the respiratory and circulatory systems.
215
Explain internal respiration.
Internal respiration, also known as cellular respiration, is the use of oxygen within mitochondria to generate ATP through oxidative phosphorylation, producing carbon dioxide as a waste product.
216
How many parts are there in the respiratory system lectures as mentioned in the content?
There are four parts in the respiratory system lectures: Part 1: Anatomical organisation, Part 2: Mechanism of breathing, Part 3: Gas exchanges in the body, and Part 4: Disorders of the respiratory system.
217
Identify the two levels at which gas exchange occurs in the respiratory system.
Gas exchange occurs at two levels: external respiration and internal respiration.
218
How does the respiratory system interact with the circulatory system?
The respiratory system interacts with the circulatory system during external respiration, where oxygen and carbon dioxide are exchanged between the atmosphere and body tissues.
219
Describe the process of external respiration.
External respiration involves air moving between the atmosphere and the lungs (pulmonary ventilation), the exchange of oxygen and carbon dioxide between lung tissue and the blood, the transportation of these gases in the blood, and the exchange of gases between systemic tissues and the blood.
220
Define internal respiration.
Internal respiration is the use of oxygen and the production of carbon dioxide by cells, primarily occurring within the mitochondria.
221
How is the respiratory system anatomically organized?
The respiratory system is organized into two major parts: the Upper Airways and the respiratory tract.
222
List the components of the conducting zone in the respiratory system.
The conducting zone includes the nose, pharynx, larynx, trachea, main (primary) bronchi, bronchioles, terminal bronchioles, respiratory bronchioles, and alveoli.
223
What is the function of the conducting zone in the respiratory system?
The conducting zone serves to filter, warm, and moisten the air as it to the lungs, and it also facilitates the passage of air to the respiratory zone.
224
Describe the anatomical features of the conducting zone.
The conducting zone features structures such as the nose, pharynx, larynx, trachea, bronchi, and bronchioles, which are designed to conduct air to the lungs.
225
What is the role of alveoli in respiratory system?
Alveoli are the sites of gas exchange in the respiratory zone, where oxygen and carbon dioxide are exchanged between the air and the blood.
226
Explain the difference between the conducting zone and the respiratory zone.
The conducting zone is responsible for the passage and conditioning of air, while the respiratory zone is where gas exchange occurs.
227
Define the pharynx and its role in the respiratory system.
The pharynx is a hollow tube that collects incoming air from the nose and passes it downward to the trachea.
228
What are the three parts of the pharynx?
The three parts of the pharynx are the nasopharynx, oropharynx, and hypopharynx.
229
Explain the function of the larynx.
The larynx, or voice box, contains vocal cords and serves as a passageway for air between the pharynx and trachea, producing voice sounds when air is breathed in and out.
230
Describe the structure and function of the trachea.
The trachea, or windpipe, is a tough, flexible tube that leads from the pharynx to the lungs, branching into the right and left bronchi, and is supported by 'C' shaped cartilage to prevent collapse.
231
What is the bronchial tree and its significance in the respiratory system?
The bronchial tree starts with two main bronchi that branch from the trachea into the lungs, continuing to branch into smaller bronchioles and eventually leading to alveoli.
232
How do bronchioles contribute to the respiratory process?
Bronchioles are small air passages that lead to alveoli, where gas exchange occurs.
233
What is the role of ciliated epithelium in the trachea?
The lining of the trachea consists of ciliated epithelium cells that trap particles with mucus and help move the mucus towards the throat.
234
Define the mucociliary escalator and its importance in the respiratory tract.
The mucociliary escalator is a mechanism in the respiratory tract where mucus-covered ciliary epithelium traps and moves particles out of the airways, helping to keep them clear.
235
Describe the function of goblet cells in the respiratory system.
Goblet cells secrete mucus, which helps trap contaminants and keep the respiratory tract moist.
236
How do cilia contribute to respiratory health?
Cilia beat to move mucus upwards, helping to remove contaminants from the respiratory tract.
237
Explain the impact of cigarette smoke on ciliary function.
Cigarette smoke impairs ciliary beating, which can hinder the removal of mucus and contaminants from the lungs.
238
What happens to cilia in the respiratory passageways due to smoking?
Smoking destroys cilia in the respiratory passageways, such as the trachea, leading to mucus accumulation.
239
Identify the role of macrophages in the alveoli.
Macrophages in the alveoli remove other inspired materials that may enter the lungs.
240
Define the structure and function of the lungs.
The lungs are paired, cone-shaped organs in the thoracic cavity responsible for gas exchange.
241
How many lobes does the right lung have compared to the left lung?.
The right lung has 3 lobes, while the left lung has 2 lobes.
242
What is the pleura and its significance in lung anatomy?
The pleura are two membranes that surround each lobe of the lungs, separating them from the chest wall.
243
Describe the composition of the chest wall.
The chest wall consists of the rib cage, sternum, thoracic vertebrae, and associated muscles and connective tissue.
244
What muscles are involved in the chest wall?
The chest wall includes intercostal muscles, internal and external intercostals, and the diaphragm.
245
Explain the function of the diaphragm in the respiratory system.
The diaphragm is a muscle that separates the chest cavity from the abdominal cavity and aids in breathing.
246
How does the chest wall protect the lungs?
The chest wall forms an airtight, continuous barrier around the lungs, providing protection and support.
247
What is the purpose of pleural fluid?
Pleural fluid lubricates the pleural membranes, allowing smooth movement of the lungs during respiration.
248
Describe the anatomy of the thoracic cavity.
The thoracic cavity houses the lungs and is surrounded by the chest wall, including the rib cage and diaphragm.
249
Describe the function of the alveoli in the respiratory system.
The alveoli are small air sacs in the lungs that facilitate the exchange of gases, allowing oxygen to enter the blood and carbon dioxide to be expelled.
250
How do the alveoli increase the efficiency of gas exchange?
The alveoli greatly increase the surface area of the lungs, which enhances the efficiency of gas exchange between the air and the blood.
251
Define the role of blood capillaries in relation to the alveoli.
Blood capillaries envelop the alveoli, allowing for the exchange of gases through a single layer of epithelium, which facilitates the transfer of oxygen and carbon dioxide.
251
Explain the mechanism of breathing in terms of lung expansion.
Breathing involves moving downward to create suction, which draws in air and expands the lungs.
252
What is the significance of the thoracic cavity in respiration?
The thoracic cavity houses the lungs and plays a crucial role in the mechanics of breathing by allowing for lung expansion and contraction.
253
How many alveoli are typically found in the human lungs?
There are approximately 300 million alveoli in the human lungs.
254
What anatomical feature allows for efficient gas exchange in the lungs?
The alveoli and capillaries are separated by only one layer of epithelium, which allows for efficient gas exchange.
