p.18
Mechanics of Breathing
What is pulmonary ventilation?
The physical movement of air in and out of the respiratory tract.
p.9
Respiratory Tract Structure
What are alveoli?
Air-filled pockets within the lungs.
p.6
Organization of the Respiratory System
What comprises the respiratory portion of the respiratory tract?
The respiratory bronchioles and alveoli.
p.9
Organization of the Respiratory System
What is the respiratory portion of the lungs?
It includes the alveoli where gas exchange occurs.
p.77
Control of Respiration
What does chemoreceptor stimulation lead to in terms of respiration?
Increased depth and rate of respiration.
p.23
Mechanics of Breathing
What happens to the rib cage during inhalation?
The ribs and sternum elevate.
p.54
Oxygen and Carbon Dioxide Transport
What happens to hemoglobin's oxygen affinity when temperature decreases?
Hemoglobin holds oxygen more tightly.
p.54
Oxygen and Carbon Dioxide Transport
In which tissues are temperature effects on hemoglobin most significant?
In active tissues generating large amounts of heat.
p.79
Control of Respiration
What is hypocapnia?
Decreased arterial P CO2.
p.4
Organization of the Respiratory System
What are the two main divisions of the respiratory system?
Upper respiratory system and lower respiratory system.
p.76
Control of Respiration
What do central chemoreceptors respond to?
P CO2 and pH of cerebrospinal fluid.
What are lung measurements used for?
To assess lung function and capacity.
p.41
Gas Exchange and Transport
How does diffusion affect gas exchange?
It allows molecules to move between gas and liquid phases.
p.47
Oxygen and Carbon Dioxide Transport
How does blood pH affect hemoglobin saturation?
Changes in blood pH can influence the binding of oxygen to hemoglobin.
What does inspiratory reserve volume (IRV) refer to?
The additional air that can be inhaled after a normal inspiration.
p.24
Respiratory Tract Structure
What is the function of pleural fluid?
It reduces friction between the pleurae during breathing.
p.72
Control of Respiration
What other sensations can affect respiration?
Pain, changes in body temperature, and abnormal visceral sensations.
p.76
Control of Respiration
What do central chemoreceptors monitor?
Cerebrospinal fluid (CSF).
p.23
Mechanics of Breathing
What occurs when the diaphragm contracts?
The volume of the thoracic cavity increases.
p.72
Control of Respiration
Where are baroreceptors located and what do they detect?
In aortic or carotid sinuses; they are sensitive to changes in blood pressure.
p.8
Respiratory Tract Structure
What surrounds each alveolus in the distal end of a single lobule?
A network of capillaries supported by elastic fibers.
p.52
Oxygen and Carbon Dioxide Transport
What is the relationship between hemoglobin, pH, and carbon dioxide concentration?
Hemoglobin's oxygen binding affinity decreases as pH decreases and carbon dioxide concentration increases.
p.69
Control of Respiration
What characterizes forced breathing?
Increased activity in the DRG stimulates the VRG and activates accessory inspiratory muscles.
What is RV trapping?
30-40% of air is trapped between the alveoli and air.
p.28
Mechanics of Breathing
What happens to pressure during inhalation?
Pressure decreases inside the lungs, allowing air to flow in.
p.3
Functions of the Respiratory System
What is one function of the respiratory system related to gas exchange?
Provides extensive gas exchange surface area between air and circulating blood.
What is the respiratory minute volume (MV or VE)?
The amount of air moved per minute.
p.41
Gas Exchange and Transport
What is the respiratory membrane?
The barrier across which gas exchange occurs.
p.42
Gas Exchange and Transport
What causes O2 to enter the blood from alveolar air?
The concentration gradient.
p.48
Oxygen and Carbon Dioxide Transport
What happens to hemoglobin saturation as partial pressure of oxygen (P O2) increases?
Higher P O2 results in greater hemoglobin saturation.
p.66
Control of Respiration
What are the apneustic and pneumotaxic centers responsible for?
Adjusting the output of respiratory rhythmicity centers.
p.68
Control of Respiration
What is the function of the Dorsal Respiratory Group (DRG)?
It acts as the inspiratory center and functions in quiet and forced breathing.
What is respiratory rate?
The number of breaths per minute.
p.5
Mechanics of Breathing
What is the function of the diaphragm in the respiratory system?
It aids in the process of breathing by contracting and relaxing to change the volume of the thoracic cavity.
p.24
Mechanics of Breathing
What happens at rest prior to inhalation?
The pressures inside and outside the lungs are equal.
p.9
Gas Exchange and Transport
Why do alveoli have a large surface area?
To increase the diffusion rate.
p.41
Gas Exchange and Transport
Where does gas exchange occur in the respiratory system?
Between blood and alveolar air.
How is the respiratory minute volume calculated?
By multiplying the respiratory rate by the tidal volume (TV).
p.32
Mechanics of Breathing
What is the role of abdominal muscles during exhalation?
They depress the ribs and compress the abdomen.
p.20
Mechanics of Breathing
What does Boyle's Law state?
The pressure of a gas is inversely proportional to its volume when temperature is held constant.
p.29
Mechanics of Breathing
What are the cyclical changes in intrapleural pressure responsible for?
Operating the respiratory pump.
p.20
Mechanics of Breathing
In Boyle's Law, what remains constant?
The temperature of the gas.
p.21
Mechanics of Breathing
What are the two main phases of a respiratory cycle?
Inspiration (inhalation) and expiration (exhalation).
p.44
Gas Exchange and Transport
Why can't blood plasma transport enough O2 or CO2?
Because it cannot meet physiological needs.
p.41
Gas Exchange and Transport
What factors does gas exchange depend on?
1. Partial pressures of the gases 2. Diffusion of molecules between gas and liquid.
p.44
Gas Exchange and Transport
What is the primary function of red blood cells (RBCs)?
To transport O2 to and CO2 from peripheral tissues.
What is the purpose of measuring lung volumes?
To evaluate respiratory health and diagnose conditions.
p.14
Respiratory Tract Structure
What is the primary function of surfactant in the lungs?
To coat alveolar surfaces and reduce surface tension.
p.57
Gas Exchange and Transport
What does carbonic acid (H2CO3) dissociate into?
Hydrogen ions (H+) and bicarbonate (HCO3-).
p.22
Mechanics of Breathing
What causes changes in the volume of the thoracic cavity?
The expansion or contraction of the diaphragm or rib cage.
p.46
Oxygen and Carbon Dioxide Transport
What does oxygen bind to in the blood?
Iron ions in hemoglobin (Hb) molecules.
p.4
Organization of the Respiratory System
What does the upper respiratory system include?
Structures above the larynx.
p.76
Control of Respiration
Where are central chemoreceptors located?
On the ventrolateral surface of the medulla oblongata.
p.3
Functions of the Respiratory System
How does the respiratory system facilitate air movement?
Moves air to and from exchange surfaces of the lungs.
p.14
Respiratory Tract Structure
What is surfactant?
An oily secretion that contains phospholipids and proteins.
p.52
Oxygen and Carbon Dioxide Transport
How does acidity affect hemoglobin's oxygen binding affinity?
Increased acidity decreases hemoglobin's oxygen binding affinity.
p.73
Control of Respiration
Which cranial nerve is associated with chemoreceptor reflexes and influences respiration?
Glossopharyngeal nerve (N IX).
p.10
Gas Exchange and Transport
What are type I pneumocytes responsible for?
Majority of gas exchange.
p.11
Gas Exchange and Transport
What is the primary function of the respiratory portion of the respiratory system?
To facilitate gas exchange.
What is Inspiratory Capacity (IC)?
Taking a deep breath after normal tidal exhalation; IC = IRV + TV.
p.52
Oxygen and Carbon Dioxide Transport
What is the Bohr effect?
The phenomenon where hemoglobin’s oxygen binding affinity is inversely related to acidity and carbon dioxide concentration.
p.42
Gas Exchange and Transport
What causes CO2 to leave the blood into alveolar air?
The concentration gradient.
p.72
Control of Respiration
What types of stimuli can irritate the respiratory system?
Irritating physical or chemical stimuli in the nasal cavity, larynx, or bronchial tree.
p.68
Control of Respiration
What does the Ventral Respiratory Group (VRG) control?
It serves as both inspiratory and expiratory center and functions only in forced breathing.
p.61
Control of Respiration
What happens to cardiac output and respiratory rates when oxygen demand rises?
They increase under neural control.
p.61
Control of Respiration
What are the components of the respiratory centers in the brain?
They have both voluntary and involuntary components.
p.71
Control of Respiration
What are the two main centers involved in the control of respiration?
The Ventral Respiratory Group (VRG) and the Dorsal Respiratory Group (DRG).
p.71
Control of Respiration
What do the VRG and DRG establish in respiration?
The basic pace and depth of respiration.
p.22
Mechanics of Breathing
What is pulmonary ventilation?
The process that causes volume changes in the thoracic cavity, leading to changes in pressure.
p.2
Functions of the Respiratory System
What are the functions of the respiratory system?
To facilitate gas exchange, regulate blood pH, and provide vocalization.
p.47
Oxygen and Carbon Dioxide Transport
What role does temperature play in hemoglobin saturation?
Temperature changes can affect the affinity of hemoglobin for oxygen.
What is expiratory reserve volume (ERV)?
The additional air that can be exhaled after a normal exhalation.
p.2
Integrated Process of Respiration
What is the integrated process of respiration?
It involves ventilation, gas exchange, and oxygen transport to tissues.
p.63
Control of Respiration
What factors influence the respiratory center's activity?
Levels of carbon dioxide, oxygen, and pH in the blood.
p.33
Integrated Process of Respiration
How does the respiratory system respond to increased oxygen demands?
By varying the respiratory rate and tidal volume.
p.6
Organization of the Respiratory System
What does the conducting portion of the respiratory tract include?
From the nasal cavity to the terminal bronchioles.
p.72
Control of Respiration
What do chemoreceptors respond to in the respiratory system?
P CO2, P O2, or pH of blood or cerebrospinal fluid.
p.69
Control of Respiration
What is the role of the DRG in quiet breathing?
It briefly stimulates inspiratory muscles.
How are lung volumes described in normal conditions?
Volumes are essentially normal.
p.3
Functions of the Respiratory System
How does the respiratory system participate in the sense of smell?
Participates in olfactory sense.
p.24
Respiratory Tract Structure
What is the role of the parietal pleura?
It lines the thoracic wall.
p.48
Oxygen and Carbon Dioxide Transport
What effect does each O2 binding have on subsequent O2 bindings?
Each O2 bound makes the next O2 binding easier.
p.29
Mechanics of Breathing
How does the respiratory pump aid the cardiovascular system?
It aids in venous return to the heart.
p.10
Respiratory Tract Structure
What type of epithelium makes up the alveolar epithelium?
Simple squamous epithelium.
p.17
Integrated Process of Respiration
What is external respiration?
The process of gas exchange between the lungs and the environment.
p.53
Oxygen and Carbon Dioxide Transport
What happens to oxygen release when blood pH decreases?
More oxygen is released; the oxygen-hemoglobin saturation curve shifts to the right.
p.79
Control of Respiration
What is the effect of decreased arterial P CO2 on chemoreceptors?
It inhibits arterial chemoreceptors.
p.1
Integrated Process of Respiration
How does the respiratory system integrate with other body systems?
It works with the circulatory system to transport gases to and from cells.
p.62
Control of Respiration
What do respiratory centers respond to?
Sensory information via respiratory reflexes.
p.4
Organization of the Respiratory System
What does the lower respiratory system include?
Structures below the larynx.
p.54
Oxygen and Carbon Dioxide Transport
How does an increase in temperature affect hemoglobin's oxygen release?
Hemoglobin releases more oxygen.
p.32
Mechanics of Breathing
Which muscles are primarily used in exhalation?
Internal intercostal and transversus thoracis muscles.
p.3
Functions of the Respiratory System
What role does the respiratory system play in protecting the body?
Protects respiratory surfaces from the outside environment.
p.47
Oxygen and Carbon Dioxide Transport
What is hemoglobin saturation?
The percentage of heme units in a hemoglobin molecule that contain bound oxygen.
p.41
Gas Exchange and Transport
What role do partial pressures play in gas exchange?
They influence the movement of gases across the respiratory membrane.
p.58
Oxygen and Carbon Dioxide Transport
What percentage of CO2 binds to hemoglobin?
23 percent is bound to amino groups of globular proteins in the hemoglobin molecule.
p.71
Control of Respiration
What is the role of the pneumotaxic center?
It modifies the pace of respiration.
p.19
Gas Exchange and Transport
What does Boyle's Law define?
The relationship between gas pressure (P) and volume (V), expressed as P = 1/V.
What is tidal volume?
The amount of air inhaled or exhaled during normal breathing.
p.14
Respiratory Tract Structure
How does surfactant contribute to lung function?
It prevents the collapse of the lung.
p.66
Control of Respiration
How does the pneumotaxic center affect respiration?
It inhibits the apneustic centers and promotes passive or active exhalation.
p.22
Mechanics of Breathing
What is the relationship between volume changes and pressure in pulmonary ventilation?
Volume changes create corresponding changes in pressure.
What is tidal volume?
The volume of air moved per breath.
p.16
Integrated Process of Respiration
What is the first process of external respiration?
Pulmonary ventilation (breathing).
p.6
Organization of the Respiratory System
What are the two main portions of the respiratory tract?
The conducting portion and the respiratory portion.
p.21
Mechanics of Breathing
How does air flow in relation to pressure?
Air flows from an area of higher pressure to an area of lower pressure.
p.15
Integrated Process of Respiration
What does external respiration involve?
All processes involved in exchanging O2 and CO2 with the environment.
p.42
Gas Exchange and Transport
What does rapid exchange in the lungs allow for?
It allows blood and alveolar air to reach equilibrium.
p.69
Control of Respiration
What happens to DRG neurons during quiet breathing?
They become inactive, allowing passive exhalation.
p.80
Functions of the Respiratory System
What are the functions of the respiratory system?
To facilitate gas exchange, regulate blood pH, and provide vocalization.
p.49
Oxygen and Carbon Dioxide Transport
What occurs when pH rises or temperature drops in relation to oxygen release?
Less oxygen is released and the curve shifts to the left.
p.57
Gas Exchange and Transport
What is the chloride shift?
An exchange mechanism where bicarbonate ions move into plasma while taking in Cl- ions without using ATP.
p.67
Control of Respiration
What part of the brain sets the pace of respiration?
The respiratory centers of the medulla oblongata.
p.74
Control of Respiration
What stimulates the chemoreceptors in the carotid bodies?
Changes in blood pH or P O2.
p.28
Mechanics of Breathing
What happens to pressure during exhalation?
Pressure increases inside the lungs, pushing air out.
p.63
Control of Respiration
What role do chemoreceptors play in respiration?
They detect changes in blood gas levels and send signals to the respiratory center.
p.53
Oxygen and Carbon Dioxide Transport
What occurs to the oxygen-hemoglobin saturation curve when pH increases?
Less oxygen is released; the curve shifts to the left.
p.74
Control of Respiration
What stimulates the chemoreceptors in the aortic bodies?
Changes in blood pH or P O2.
p.23
Mechanics of Breathing
What is the effect of elevating the rib cage or depressing the diaphragm?
It increases the volume of the thoracic cavity.
p.48
Oxygen and Carbon Dioxide Transport
What does the oxygen-hemoglobin saturation curve represent?
A graph relating the saturation of hemoglobin to the partial pressure of oxygen.
How is Vital Capacity (VC) defined?
Taking a deep breath in and out; VC = IRV + TV + ERV.
p.49
Oxygen and Carbon Dioxide Transport
What is the standard condition for the oxygen-hemoglobin saturation curve?
Normal blood at pH 7.4 and 37 °C.
p.44
Gas Exchange and Transport
How do red blood cells assist in gas exchange?
By removing O2 and CO2 from plasma, allowing gases to diffuse into blood.
p.15
Integrated Process of Respiration
What occurs during internal respiration?
Uptake of O2 and production of CO2 within individual cells.
p.80
Organization of the Respiratory System
What is the organization of the respiratory system?
It includes the upper and lower respiratory tracts, lungs, and associated structures.
p.8
Respiratory Tract Structure
What is the function of smooth muscle cells in respiratory bronchioles?
They can change the diameter of these airways.
p.5
Organization of the Respiratory System
What are the two main divisions of the respiratory system?
Upper Respiratory System and Lower Respiratory System.
p.1
Organization of the Respiratory System
What are the main components of the respiratory system?
Nasal cavity, pharynx, larynx, trachea, bronchi, and lungs.
p.27
Mechanics of Breathing
What is the effect of low compliance on breathing?
Low compliance requires greater force to expand the lungs.
p.53
Oxygen and Carbon Dioxide Transport
What is the effect of pH on oxygen-hemoglobin saturation?
A decrease in pH leads to increased oxygen release, while an increase in pH leads to decreased oxygen release.
What measurements are used to assess lung function?
Tidal volume, vital capacity, and total lung capacity.
p.27
Mechanics of Breathing
How does fibrosis affect lung compliance?
Fibrosis decreases compliance, making the lungs less expandable.
p.75
Respiratory Centers and Reflex Controls
What are the two main groups of respiratory rhythmicity centers in the medulla oblongata?
Dorsal respiratory group (DRG) and Ventral respiratory group (VRG).
p.31
Mechanics of Breathing
What is the function of external intercostal muscles?
To elevate the ribs during inhalation.
p.12
Respiratory Tract Structure
What is the significance of elastic fibers in the alveoli?
They allow the alveoli to expand and contract during breathing.
p.1
Oxygen and Carbon Dioxide Transport
How is oxygen transported in the blood?
Primarily bound to hemoglobin in red blood cells.
p.64
Control of Respiration
What effect does a decrease in pneumotaxic output have on respiration?
It slows the respiratory pace but increases the depth of respiration.
p.60
Oxygen and Carbon Dioxide Transport
How is carbon dioxide transported from peripheral tissues to the lungs?
CO2 is picked up by red blood cells and transported back to the pulmonary capillaries.
p.15
Integrated Process of Respiration
What are the two integrated processes of respiration?
External respiration and internal respiration.
p.77
Control of Respiration
What is a characteristic of chemoreceptor stimulation?
It is subject to adaptation.
p.32
Mechanics of Breathing
How do abdominal muscles assist in exhalation?
By compressing the abdomen and forcing the diaphragm upward.
p.48
Oxygen and Carbon Dioxide Transport
Why is the oxygen-hemoglobin saturation curve not a straight line?
Because hemoglobin changes shape each time a molecule of O2 is bound.
What is resting tidal volume (TV)?
The volume of air inhaled or exhaled during a normal respiratory cycle, or quiet breathing.
p.66
Control of Respiration
What does the apneustic center do?
Provides continuous stimulation to the dorsal respiratory group (DRG) center.
p.63
Control of Respiration
What is the primary function of the respiratory center?
To regulate the rate and depth of breathing.
p.62
Control of Respiration
What part of the brain contains the respiratory centers?
The medulla oblongata and pons.
p.19
Gas Exchange and Transport
What happens to gas molecules in a contained gas when external pressure increases?
External pressure forces molecules closer together.
p.63
Control of Respiration
Where is the respiratory center located?
In the brainstem, specifically in the medulla oblongata and pons.
p.66
Control of Respiration
What two phases of respiration are regulated by the centers in the pons?
Inspiration and expiration.
What is minimal volume in the context of lung measurements?
The volume of air remaining in a collapsed lung.
p.24
Respiratory Tract Structure
What is the visceral pleura?
It covers the lungs themselves.
p.50
Oxygen and Carbon Dioxide Transport
What is the relationship between O2 pressure (P) and oxyhemoglobin saturation?
As O2 pressure increases, oxyhemoglobin saturation also increases.
What is the resting tidal volume (TV)?
The amount of air inhaled or exhaled during normal breathing.
p.10
Mechanics of Breathing
What is the function of surfactant in the alveoli?
To reduce surface tension and prevent alveolar collapse.
p.78
Control of Respiration
What is the effect of increased respiratory rate on arterial P CO2?
It decreases arterial P CO2.
p.78
Control of Respiration
Where are the chemoreceptors that respond to arterial P CO2 located?
In the medulla oblongata.
p.12
Respiratory Tract Structure
What role do alveolar macrophages play in the lungs?
They help in the immune response by engulfing pathogens and debris.
p.31
Mechanics of Breathing
What are primary respiratory muscles?
Muscles that are primarily responsible for the act of breathing.
p.49
Oxygen and Carbon Dioxide Transport
What happens to the oxygen-hemoglobin saturation curve when pH drops or temperature rises?
More oxygen is released and the curve shifts to the right.
p.2
Organization of the Respiratory System
What is the organization of the respiratory system?
It includes the upper and lower respiratory tracts, lungs, and associated structures.
p.48
Oxygen and Carbon Dioxide Transport
How does the oxygen-hemoglobin saturation curve benefit hemoglobin at low oxygen levels?
It allows hemoglobin to bind O2 when O2 levels are low.
p.1
Functions of the Respiratory System
What is the primary function of the respiratory system?
To facilitate gas exchange, providing oxygen to the body and removing carbon dioxide.
p.19
Gas Exchange and Transport
What is the effect of gas molecule movement in a container?
The movement of gas molecules exerts pressure on the container.
p.58
Oxygen and Carbon Dioxide Transport
Why does carbon dioxide have higher solubility in blood than oxygen?
Due to its chemical properties and interactions with blood components.
p.8
Respiratory Tract Structure
What are the components of the basic structure of the distal end of a single lobule?
Alveolus, alveolar sac, alveolar duct, and respiratory bronchiole.
p.56
Oxygen and Carbon Dioxide Transport
How is carbon dioxide transported in the bloodstream?
Three ways: converted to carbonic acid, bound to hemoglobin, and dissolved in plasma.
p.62
Control of Respiration
What is the function of the respiratory centers?
To regulate respiratory muscles.
p.79
Control of Respiration
What occurs when chemoreceptors are inhibited?
Decreased stimulation of respiratory muscles.
p.79
Control of Respiration
What is the result of decreased respiratory rate?
Decreased elimination of CO2 at the alveoli.
p.16
Integrated Process of Respiration
What is transported between alveolar capillaries?
Oxygen (O2) and carbon dioxide (CO2).
p.67
Control of Respiration
What is the role of the ventral respiratory group (VRG)?
It is involved in the active process of breathing.
p.65
Control of Respiration
What is the role of the inspiratory center of the DRG?
It contains neurons that control lower motor neurons innervating the external intercostal muscles and the diaphragm, functioning in every respiratory cycle.
p.1
Gas Exchange and Transport
What is the process of gas exchange in the lungs?
Oxygen diffuses into the blood, and carbon dioxide diffuses out.
p.27
Mechanics of Breathing
How does emphysema affect lung compliance?
Emphysema increases compliance, making the lungs more expandable.
p.31
Mechanics of Breathing
What are accessory respiratory muscles?
Muscles that assist in breathing but are not the primary muscles.
p.60
Gas Exchange and Transport
What is the chemical reaction that occurs with carbon dioxide in the blood?
CO2 + H2O ↔ H2CO3 ↔ HCO3− + H+.
What does vital capacity measure?
The maximum amount of air a person can exhale after a maximum inhalation.
p.20
Mechanics of Breathing
How is Boyle's Law mathematically expressed?
P1V1 = P2V2, where P is pressure and V is volume.
What is residual volume?
The amount of air remaining in the lungs after a forced exhalation.
p.50
Oxygen and Carbon Dioxide Transport
What does the % saturation of Hb represent?
The percentage of hemoglobin that is saturated with oxygen.
p.28
Mechanics of Breathing
How can pressure changes be measured?
They can be measured inside or outside the lungs.
p.75
Respiratory Centers and Reflex Controls
Which cranial nerves are involved in diaphragm control?
N IX (Glossopharyngeal) and N X (Vagus).
p.2
Gas Exchange and Transport
What is the process of gas exchange and transport?
It occurs in the alveoli where oxygen is absorbed and carbon dioxide is released.
p.80
Gas Exchange and Transport
What is the process of gas exchange and transport?
Oxygen is absorbed into the blood, and carbon dioxide is expelled from the blood.
p.16
Integrated Process of Respiration
Where else is O2 and CO2 transported besides alveolar capillaries?
Between capillary beds in other tissues.
p.78
Control of Respiration
What is the outcome of stimulating respiratory muscles due to increased arterial P CO2?
Increased respiratory rate and CO2 elimination at the alveoli.
p.12
Gas Exchange and Transport
How do capillaries interact with alveoli?
A single capillary may be involved in gas exchange with several alveoli simultaneously.
p.1
Respiratory Centers and Reflex Controls
What reflex controls help protect the respiratory system?
Coughing and sneezing reflexes.
p.65
Control of Respiration
What is the primary function of the DRG?
It is mainly concerned with inspiration.
p.47
Oxygen and Carbon Dioxide Transport
How does metabolic activity within RBCs influence hemoglobin saturation?
Increased metabolic activity can lower pH and increase temperature, affecting oxygen binding.
p.24
Mechanics of Breathing
What does 'P outside = P inside' indicate?
Pressure outside and inside are equal, so no air movement occurs.
What is residual volume (RV)?
The volume of air remaining in the lungs after maximal exhalation.
p.17
Functions of the Respiratory System
What is the primary function of the lungs in respiration?
To facilitate gas exchange, specifically oxygen and carbon dioxide.
p.1
Mechanics of Breathing
What is the mechanics of breathing?
Involves inhalation and exhalation through changes in lung volume and pressure.
p.79
Control of Respiration
How does decreased arterial P CO2 affect the rate of respiration?
It decreases the rate of respiration.
p.5
Functions of the Respiratory System
What is the role of the olfactory bulb?
It is involved in the sense of smell.
p.65
Control of Respiration
What do pacemaker cells in the medulla oblongata do?
They generate cycles of contraction and relaxation in the diaphragm.
p.26
Mechanics of Breathing
What causes air to flow out of the lungs?
Increased pressure inside the thoracic cavity.
p.31
Mechanics of Breathing
Which muscle is involved in the protraction of the scapula and assists in breathing?
Serratus anterior muscle.
p.29
Mechanics of Breathing
What is tidal volume (TV or V T)?
The amount of air moved in and out of the lungs in a single respiratory cycle.
p.69
Control of Respiration
What occurs after inhalation during forced breathing?
Active exhalation takes place.
p.2
Mechanics of Breathing
What are the mechanics of breathing?
Involves inhalation and exhalation through diaphragm and intercostal muscles.
p.5
Gas Exchange and Transport
What is the role of the alveoli in the respiratory system?
They are the sites where gas exchange occurs.
p.80
Mechanics of Breathing
What are the mechanics of breathing?
Involves inhalation and exhalation through diaphragm and intercostal muscles.
p.56
Oxygen and Carbon Dioxide Transport
What percentage of carbon dioxide is converted to carbonic acid?
Not specified in the text, but it is one of the three transport methods.
p.17
Mechanics of Breathing
What is pulmonary ventilation?
The process of moving air in and out of the lungs.
p.27
Mechanics of Breathing
What is the effect of high compliance on breathing?
High compliance requires less force to expand the lungs.
p.75
Respiratory Centers and Reflex Controls
What do stretch receptors in the lungs signal?
They provide afferent signals to the respiratory centers.
p.64
Control of Respiration
What happens to respiratory cycles if the brain stem above the pons is damaged?
Essentially normal respiratory cycles continue.
p.12
Respiratory Tract Structure
What is the function of Type II pneumocytes?
They produce surfactant, which reduces surface tension in the alveoli.
p.59
Gas Exchange and Transport
What is the chloride shift in red blood cells?
HCO3− moves out of RBC in exchange for Cl−.
p.51
Oxygen and Carbon Dioxide Transport
How does the dissociation of carbonic acid affect pH?
Hydrogen ions can diffuse out of RBC, lowering pH.
p.7
Gas Exchange and Transport
What are the tiny air sacs where gas exchange occurs in the lungs?
Alveoli in a pulmonary lobule.
p.68
Control of Respiration
In which type of breathing does the Dorsal Respiratory Group (DRG) function?
In both quiet and forced breathing.
p.19
Mechanics of Breathing
What is pulmonary ventilation?
The process of moving air in and out of the lungs.
p.63
Control of Respiration
How does the body respond to increased carbon dioxide levels?
By increasing the rate and depth of breathing.
p.2
Control of Respiration
How is respiration controlled?
Through neural and chemical mechanisms that regulate breathing rate and depth.
p.10
Respiratory Tract Structure
What is the characteristic of type I pneumocytes?
They are thin and delicate.
p.26
Mechanics of Breathing
What happens to the rib cage during exhalation?
It returns to its original position.
p.43
Gas Exchange and Transport
What is the significance of the respiratory membrane?
It allows for the exchange of gases between the alveoli and pulmonary capillaries.
p.17
Integrated Process of Respiration
What occurs during internal respiration?
The exchange of gases between the blood and the tissues.
p.27
Mechanics of Breathing
What is the relationship between compliance and pulmonary ventilation?
Compliance affects the ease of pulmonary ventilation; higher compliance facilitates easier ventilation.
p.60
Oxygen and Carbon Dioxide Transport
Where does oxygen delivery occur in the body?
In the systemic capillaries to cells in peripheral tissues.
p.80
Integrated Process of Respiration
What is the integrated process of respiration?
It involves ventilation, gas exchange, and oxygen transport to tissues.
p.30
Mechanics of Breathing
Which muscles assist in inhalation alongside the diaphragm?
External intercostal muscles.
What is total lung volume divided into?
A series of volumes and capacities useful in diagnosing problems.
p.18
Mechanics of Breathing
What are the effects of pulmonary ventilation?
It has several important physiological effects.
p.67
Control of Respiration
What is the function of the dorsal respiratory group (DRG)?
It helps regulate the rhythm of breathing.
p.64
Control of Respiration
What are the higher centers that can alter respiratory activity?
Cerebral cortex, limbic system, and hypothalamus.
p.79
Control of Respiration
What happens to arterial P CO2 when the rate of respiration decreases?
Arterial P CO2 increases.
p.55
Oxygen and Carbon Dioxide Transport
What is the effect of temperature on oxyhemoglobin saturation?
Higher temperatures lead to lower saturation levels.
p.17
Oxygen and Carbon Dioxide Transport
What is the significance of CO2 transport in respiration?
To carry carbon dioxide from the tissues back to the lungs for exhalation.
p.51
Oxygen and Carbon Dioxide Transport
What does carbonic acid dissociate into?
Hydrogen ion (H+) and bicarbonate ion (HCO3-).
p.75
Respiratory Centers and Reflex Controls
What does the key 'Stimulation = Inhibition' refer to?
It indicates the relationship between respiratory centers and their control mechanisms.
p.31
Mechanics of Breathing
Which muscle helps stabilize the rib cage during breathing?
Transversus thoracis muscle.
p.65
Control of Respiration
What types of receptors influence the activities of the DRG?
Chemoreceptors, baroreceptors, and stretch receptors.
p.16
Integrated Process of Respiration
What is the second process of external respiration?
Gas diffusion across membranes and capillaries.
p.25
Mechanics of Breathing
What effect does inhalation have on the size of the thoracic cavity?
It increases the size of the thoracic cavity.
What are lung measurements?
They include tidal volume, vital capacity, and residual volume.
p.5
Respiratory Tract Structure
What is the purpose of the epiglottis?
To prevent food from entering the trachea during swallowing.
p.43
Gas Exchange and Transport
What is the role of the pulmonary capillary in respiration?
It facilitates gas exchange between the alveolus and blood.
p.59
Gas Exchange and Transport
How is H+ removed from the bloodstream?
By buffers, especially hemoglobin (Hb).
p.50
Oxygen and Carbon Dioxide Transport
What is the trend in oxyhemoglobin saturation as O2 pressure decreases?
Oxyhemoglobin saturation decreases.
p.65
Control of Respiration
What are the two subdivisions of the respiratory rhythmicity centers?
Dorsal respiratory group (DRG) and ventral respiratory group (VRG).
p.75
Respiratory Centers and Reflex Controls
What is the role of the diaphragm in respiration?
It is a primary muscle that controls breathing.
p.10
Respiratory Tract Structure
What cells patrol the alveolar epithelium?
Alveolar macrophages (dust cells).
p.67
Control of Respiration
What are the two groups of the respiratory centers in the medulla oblongata?
Dorsal respiratory group (DRG) and Ventral respiratory group (VRG).
p.51
Oxygen and Carbon Dioxide Transport
What is the Bohr effect?
The effect of pH on the hemoglobin saturation curve, influenced by CO2.
p.25
Mechanics of Breathing
What causes air to flow into the lungs during inhalation?
The pressure outside the lungs is greater than the pressure inside.
p.31
Mechanics of Breathing
Which muscle assists in elevating the rib cage during inhalation?
Sternocleidomastoid muscle.
p.5
Respiratory Tract Structure
What are bronchioles?
They are the smallest branches of the bronchial tubes that lead to the alveoli.
What is residual volume (RV)?
The amount of air remaining in the lungs after a forced exhalation.
p.64
Control of Respiration
What are the functions of the pneumotaxic centers?
Inhibit apneustic centers and promote passive or active exhalation.
p.55
Oxygen and Carbon Dioxide Transport
At what temperature is the oxyhemoglobin saturation curve measured?
At 10 °C, 20 °C, 38 °C, and 43 °C.
p.64
Control of Respiration
What is the role of apneustic centers during forced breathing?
They adjust the degree of stimulation in response to sensory information about lung inflation.
p.12
Gas Exchange and Transport
What is the role of endothelial cells in the alveolar-capillary interface?
They form the lining of capillaries and facilitate gas exchange.
p.60
Gas Exchange and Transport
What happens to carbon dioxide in the pulmonary capillaries?
It is converted to bicarbonate (HCO3−) and then released into the alveolar air space.
p.27
Mechanics of Breathing
What does compliance indicate in the context of the lungs?
It indicates the expandability or stretch and expand capability of the lungs.
What are lung measurements?
They include tidal volume, vital capacity, and total lung capacity.
p.16
Integrated Process of Respiration
Where does gas diffusion occur in external respiration?
Across membranes and capillaries.
p.75
Respiratory Centers and Reflex Controls
What type of receptors provide afferent signals to the respiratory centers?
Chemoreceptors and baroreceptors from carotid and aortic sinuses.
p.17
Oxygen and Carbon Dioxide Transport
What is the role of O2 transport in respiration?
To carry oxygen from the lungs to the tissues.
p.80
Control of Respiration
How is respiration controlled?
Through neural and chemical mechanisms that regulate breathing rate and depth.
p.17
Gas Exchange and Transport
What is gas diffusion in the context of respiration?
The movement of gases from areas of higher concentration to areas of lower concentration.
p.56
Oxygen and Carbon Dioxide Transport
What is the role of hemoglobin in gas transport?
It binds to oxygen for transport in the bloodstream.
p.65
Control of Respiration
When does the VRG function?
It functions only when breathing demands increase and accessory muscles become involved.
p.64
Control of Respiration
How does an increase in pneumotaxic output affect respiration?
It quickens the pace of respiration by shortening inhalation duration.
p.1
Respiratory Tract Structure
What structures make up the respiratory tract?
The upper and lower respiratory tracts, including the nasal passages and lungs.
p.30
Mechanics of Breathing
What role do accessory muscles play in breathing?
They assist in elevating the ribs.
p.78
Control of Respiration
What do increased levels of arterial P CO2 stimulate?
Chemoreceptors that accelerate breathing cycles.
What does expiratory reserve volume (ERV) refer to?
The additional amount of air that can be forcibly exhaled after the expiration of a normal tidal volume.
p.27
Mechanics of Breathing
What factors affect lung compliance?
Connective tissue structure of the lungs, level of surfactant production, and mobility of the thoracic cage.
p.5
Functions of the Respiratory System
What is the function of the nasal cavity?
To filter, warm, and humidify the air we breathe.
p.50
Oxygen and Carbon Dioxide Transport
What happens to oxyhemoglobin saturation at 20 mm Hg O2 pressure?
It drops to approximately 35%.
What is inspiratory reserve volume (IRV)?
The additional amount of air that can be inhaled after a normal tidal inhalation.
p.64
Control of Respiration
What do apneustic centers promote?
Inhalation by stimulating the DRG (Dorsal Respiratory Group).
p.31
Mechanics of Breathing
What is the function of the external oblique muscle in respiration?
It assists in forced expiration.
p.31
Mechanics of Breathing
What is the role of the internal oblique muscle in respiration?
It aids in forced expiration.
p.7
Organization of the Respiratory System
What is the functional unit of the lung that includes the alveoli?
Bronchopulmonary segment.
p.60
Oxygen and Carbon Dioxide Transport
What is the significance of hemoglobin (Hb) in gas transport?
Hemoglobin binds to oxygen and carbon dioxide, facilitating their transport in the blood.
p.59
Gas Exchange and Transport
What is formed when 23% of CO2 binds to hemoglobin (Hb)?
Carbaminohemoglobin (Hb•CO2).
p.1
Control of Respiration
What controls the rate and depth of breathing?
The respiratory centers in the brainstem.
p.65
Control of Respiration
What is the significance of the pre-Bötzinger complex?
It is essential to all forms of breathing, although its mechanisms are poorly understood.
p.31
Mechanics of Breathing
What role do internal intercostal muscles play?
They assist in forced exhalation by depressing the ribs.
p.65
Control of Respiration
How do respiratory rhythmicity centers set the pace of respiration?
By adjusting the activities of pacemaker cells and coordinating the activities of additional respiratory muscles.
p.60
Oxygen and Carbon Dioxide Transport
What is the primary mechanism for oxygen transport in the blood?
Oxygen is picked up by hemoglobin (Hb) in red blood cells in the pulmonary capillaries.
p.60
Gas Exchange and Transport
What is the role of the chloride shift in gas transport?
It helps maintain ionic balance during carbon dioxide transport in red blood cells.
