Pulmonary system
What is one function of the type II alveolar cells? production of surfactant lining the pleural space phagocytizing bacteria and other foreign particles make up the majority of the epithelial wall of the alveoli secretion of mucus
production of surfactant
Review the sequence of events during inspiration the ___1___ and inspiratory muscles contract, causing the ___2___ to expand ___3___ becomes more sub atmospheric compared to preinspiratory values ___4___ increases causing lungs to expand ___5___ becomes sub atmospheric Air flows into the ___6___
1. Diaphragm 2. thorax 3. intrapleural pressure 4. transpulmonary pressure 5. alveolar pressure 6. lungs
Thinking of the lung tissues as occurs with the disease ____1___ decreases lung compliance increased concentration of ___2___ secreted by type 2 alveolar cells increases lung compliance ____3____ within the fluid layer winning the alveoli decreases lung compliance ___4___ is characterized by the destruction of the alveolar walls leading to increases in compliance decreased diameter of bronchioles die to airway inflammation as occurs during an ___5___ decreases air flow increased resistance of bronchioles due to excessive mucus production from chronic bronchitis ___6___ air flow Bronchodilation ___7___ air flow
1. cystic fibrosis 2. surfactant 3. surface tension 4. emphysema 5. asthma attack 6. decreases 7. increases
Review the sequence of events during passive expiration The ___1___ and inspiratory muscles stop contracting causing the ___2___ to recoil inward ___3___ increases back toward its preinspiration value ___4___ moves back toward its preinspiration value allowing the lungs to passively recoil toward their preinspiration size air in the ___5___ sacs become compressed ___6___ becomes greater than ___7___ air flows out of the ___8___
1. diaphragm 2. chest wall 3. intrapleural pressure 4. transpulmonary pressure 5. alveolar 6. alveolar pressure 7. atmospheric pressure 8. lungs
The partial pressure of oxygen in the alveolar gas is affected by certain situations. Classify each of the following conditions as causing an increase, decrease, or no change in alveolar Po2. 1. Increased alveolar ventilation and unchanged metabolism 2. decreased alveolar ventilation and unchanged metabolism 3. decreased metabolism and unchanged alveolar ventilation 4. Increased metabolism and unchanged alveolar ventilation 5. breathing air with low PO2 6. proportional increases in metabolism and alveolar ventilation
1. increases PO2 2. Decreases PO2 3. Increases PO2 4. Decreases PO2 5. Decreases PO2 6. No change
After expiration and before the next inspiration begins, which is TRUE about the pressures involved in respiration? Alveolar pressure is equal to atmospheric pressure. Alveolar pressure is equal to intrapleural pressure. Intrapleural pressure is equal to atmospheric pressure. Alveolar pressure is greater than atmospheric pressure. Alveolar pressure is less than atmospheric pressure.
Alveolar pressure is equal to atmospheric pressure.
Which of the following occurs during expiration? Alveolar pressure rises above atmospheric pressure. Alveolar pressure falls below atmospheric pressure. A decrease in alveolar volume causes a decrease in alveolar pressure. An increase in alveolar volume causes a decrease in alveolar pressure. An increase in alveolar volume causes an increase in alveolar pressure.
Alveolar pressure rises above atmospheric pressure.
Which of the following best describes hypoventilation? Alveolar ventilation is decreased, but whole-body metabolism is unchanged. The frequency of breathing is below normal, but the whole-body metabolism is unchanged. Tidal volume is above normal, but whole-body metabolism is unchanged. Tidal volume is below normal, but whole-body metabolism is unchanged. The frequency of breathing is increased above normal, but whole-body metabolism is unchanged.
Alveolar ventilation is decreased, but whole-body metabolism is unchanged.
During inhalation/inspiration, the total alveolar volume decreases. True False
False
During the respiratory cycle, the alveolar pressure is never equal to the pressure in the atmosphere outside the body. True False
False
Exhalation/expiration of air from the lungs requires contraction of the exhalatory/expiratory intercostal muscles. True False
False
If the parietal pleura is cut during surgery, the lung on the side of the cut will expand and the chest wall will be compressed. True False
False
Which of these occurs during inspiration? A decrease in alveolar volume causes an increase in alveolar pressure. A decrease in alveolar volume causes a decrease in alveolar pressure. An increase in alveolar volume causes an increase in alveolar pressure. Alveolar pressure increases above atmospheric pressure. An increase in alveolar volume causes a decrease in alveolar pressure.
An increase in alveolar volume causes a decrease in alveolar pressure.
Ischemic Hypoxia
Blood flow to the tissues is too low
Infants born prematurely frequently develop respiratory distress syndrome of the newborn because they have too few alveoli to exchange O2 and CO2 efficiently. True False
False
Most of the O2 carried in the blood is dissolved in plasma. True False
False
The dead space volume of the lungs is directly proportional to the minute ventilation. True False
False
The diaphragm is a large sheet of smooth muscle that separates the thoracic cavity from the abdomen. True False
False
The heart is bathed by intrapleural fluid. True False
False
The rhythmic contractions and relaxations of the inspiratory muscles are dependent upon spontaneous depolarizations of the diaphragm. True False
False
Which of these would tend to increase ventilation? higher than normal blood pH lower than normal blood PCO2 breathing air with increased PCO2 iron-deficiency anemia breathing carbon monoxide
breathing air with increased PCO2
If metabolism changes, which of the following quantities must change proportionately in order to maintain normal oxygen and carbon dioxide levels in the systemic arterial blood? breathing frequency x tidal volume breathing frequency x (tidal volume - dead space volume) breathing frequency tidal volume x breathing frequency tidal volume
breathing frequency x (tidal volume - dead space volume)
anemic hypoxia
hemoglobin concentration is reduced
During inhalation, air passes through either the ___1___ or mouth into the ___2___ pharynx, a passage common to both air and food the pharynx branches into 2 paths: the ___3___ through which food passes to the stomach and the ____4____, which is part of the airways and houses the vocal cords the larynx opens into a long tube, the ___5___ which in turn branches into 2 ___6___ one of which enters each lung. Rings of cartilage support the walls. The first airway branches that no longer contain cartilage are ___7___ bronchioles continue branching into ___8___ which are final airways of the ___9___ zone. This zone contains no ___10___ and therefore has no gas exchange with the blood. alveoli first begin to appear attactched to the walls of the ___11___ which then branch into the ___12___ and the airways finally end in grape like clusters consisting of alveoli which are called ___13___ These last 3 structures make up the ___14___ zone, which is the region where gases exchange with the blood
1. nose 2. pharynx 3. esophagus 4. larynx 5. trachea 6. bronchi 7. bronchioles 8. terminal bronchioles 9. conducting 10. alveoli 11. respiratory bronchioles 12. alveolar ducts 13. alveolar sacs 14. respiratory
Assume that end diastolic volume of the left ventricle is 150 ml and the end systolic volume is 50 ml. The stroke volume is ____ ml and the ejection fraction is _____ %. 100 ml; 66% 50 ml; 66% 100 ml; 33% 50 ml; 33%
100 ml; 66%
When lying down, a subject's respiratory rate is 12 breaths per minute, his anatomical dead space is 150 ml, and his minute ventilation is 7 L/min. Which of these is closest to his alveolar ventilation in liters per minute? 3.0 4.2 0.583 6.0 5.2
5.2
During a physical examination, Joe learns that his resting tidal volume is 550 ml; his average resting respiratory rate is 15 breaths per minute; his total lung capacity is 6000 ml; and his anatomic dead space is 150 ml. Joe's resting alveolar ventilation is 4.2 L/min 1.8 L/min 6.0 L/min 72.0 L/min 0.5 L/min
6.0
Histotoxic hypoxia
Chemical interferes with metabolic machinery of the cells
During an unforced exhalation/expiration, which would NOT be true? intrapleural pressure is greater than alveolar pressure the diaphragm relaxes intrapleural pressure becomes less negative lung volume decreases alveolar pressure is greater than atmospheric pressure
Intrapleural pressure is greater than alveolar pressure
If the right side of the chest wall is punctured leading to a pneumothorax on the right side of the thorax: air will enter the intrapleural space on the left side of the thorax intrapleural pressure on the left side of the thorax will decrease both the right and left lung will collapse intrapleural pressure on the right side of the thorax will increase
Intrapleural pressure on the right side of the thorax will increase
Which is TRUE about the pleural sac? It is continuous with the atmosphere and protects the lungs from infection. It is a closed, air-filled space surrounding both lungs that has a negative pressure compared to atmospheric pressure. It is a closed sac surrounding each lung that contains only a tiny volume of lubricating fluid. It is a closed sac surrounding each lung and contains a large volume of surfactant. It is bounded by pleural membranes that are very thin, which allows for abundant gas exchange.
It is a closed sac surrounding each lung that contains only a tiny volume of lubricating fluid.
Which is normally TRUE about the intrapleural pressure? It alternates between being less than, and greater than, atmospheric pressure. It is always the same as atmospheric pressure during a passive exhale. It is between +5 and +10 mm Hg above atmospheric pressure at functional residual capacity. It is lower than alveolar pressure. During a passive exhale, it increases to a value above atmospheric pressure.
It is lower than alveolar pressure.
Which is a TRUE statement about minute ventilation and alveolar ventilation? When alveolar ventilation increases, minute ventilation always increases. Minute ventilation and alveolar ventilation always change proportionately. Alveolar ventilation is always greater than minute ventilation Minute ventilation is always greater than alveolar ventilation. When minute ventilation increases, alveolar ventilation always increases.
Minute ventilation is always greater than alveolar ventilation.
Which of the following is NOT true regarding ventilation-perfusion inequality? It may result from increased alveolar dead space. It is increased from normal in patients with emphysema. It is caused by too little or too much blood flow relative to ventilation. No inequality exists in normal lungs. It is caused by too little or too much ventilation relative to blood flow.
No inequality exists in normal lungs.
Regarding the partial pressures of O2 and CO2, which of the following statements is NOT true in a normal person at rest? Atmospheric PO2 is greater than alveolar PO2. The PO2 in systemic arteries is typically greater than the alveolar PO2. PCO2 in the systemic veins is greater than systemic arterial PCO2. The PCO2 in air is less than alveolar PCO2. PCO2 in the pulmonary arteries is greater than pulmonary venous PCO2.
The PO2 in systemic arteries is typically greater than the alveolar PO2.
A spinal cord injury has led to paralysis of both the diaphragm and the intercostal muscles. The injury must have occurred between C5 and C6 above C3 between C7 and T1 below T8 below T1
above C3
Which correctly describes the cause of the increase in alveolar ventilation that occurs when a person ascends to high altitude? The decrease in PO2 of inspired air decreases alveolar and arterial PO2, stimulating the peripheral chemoreceptors. The decrease in the total barometric pressure at high altitude causes hypocapnea, which stimulates peripheral chemoreceptors. The decrease in PCO2 of inspired air decreases alveolar PCO2, stimulating the peripheral chemoreceptors. The decrease in total atmospheric pressure causes a greater negative pressure in the intrapleural space, resulting in deeper and more frequent breathing. The decrease in PCO2 of inspired air decreases alveolar PCO2, stimulating the central chemoreceptors.
The decrease in PO2 of inspired air decreases alveolar and arterial PO2, stimulating the peripheral chemoreceptors.
As the volume in the alveoli increases, the pressure decreases. True False
True
During inhalation/inspiration, the diaphragm contracts and the alveolar pressure is less than atmospheric pressure; during exhalation/expiration, the diaphragm relaxes and the alveolar pressure is greater than atmospheric pressure. True False
True
Each lung is enclosed within a separate pleural cavity. True False
True
Hyperventilation can occur either with an increase or decrease in breathing frequency. True False
True
Nonrespiratory functions of the lungs include acting as "filters" for removing certain chemicals and blood clots. True False
True
The diameter of the airways in normal lungs is generally great enough that little resistance is offered to airflow. True False
True
When a person hyperventilates, there are lower than normal levels of PCO2 and hydrogen ion in arterial blood, a condition called respiratory alkalosis. True False
True
Which of the following does NOT contribute to the interface or barrier between alveolar air and pulmonary capillary blood? Type I alveolar epithelial cell Type II alveolar epithelial cell pulmonary endothelial cell interstitial layer between alveolar epithelial cell and pulmonary capillary endothelium layer of fluid containing surfactant on the surface of the alveolus
Type II alveolar epithelial cell
Assume that a region of the lung is under ventilated due to an obstruction of the airways to this region of the lung. Which of the following correctly describes the events that follow? alveolar hypoxia would occur in this region of the lung leading to pulmonary vasoconstriction and a decrease in blood flow to this region of the lung alveolar hypoxia would occur in this region of the lung leading to pulmonary vasodilation and an increase in blood flow to this region of the lung alveolar PO2 would increase in this region of the lung leading to pulmonary vasoconstriction and a decrease in blood flow to this region of the lung alveolar PO2 would increase in this region of the lung leading to pulmonary vasodilation and an increase in blood flow to this region of the lung
alveolar hypoxia would occur in this region of the lung leading to pulmonary vasoconstriction and a decrease in blood flow to this region of the lung
Which of these does NOT increase during heavy exercise? minute ventilation arterial PCO2 body heat production oxygen extraction from the blood by muscles oxygen delivery to muscles
arterial PCO2
hypoxic hypoxia
arterial PO2 is reduced
Alveolar hypoxia throughout the entire lung leads to constriction of pulmonary arterioles both a and c are true both b and c are true increases pulmonary arterial blood pressure leads to dilation of pulmonary arterioles
both a and c are true
In which form is most of the oxygen carried in arterial blood? bound to myoglobin dissolved in the plasma bound to hemoglobin converted to HCO3- dissolved in the cytosol of erythrocytes
bound to hemoglobin
An individual is floating on the surface of the water and breathing through a snorkel. If the individual maintained the same respiratory rate and tidal volume as he / she had prior to breathing through the snorkel, then alveolar ventilation would increase decrease remain unchanged may increase or decrease depending on the volume of the snorkel
decrease
If a lung disease leads to increased mismatching of ventilation to perfusion (i.e., increased ventilation : perfusion heterogeneities), one would expect an decrease in arterial PCO2 decrease in alveolar PO2 decrease in arterial PO2 increase in arterial PO2 increase in mixed venous PO2
decrease in arterial PO2
Which of these causes inhalation/inspiration? flattening (downward movement) of the diaphragm alveolar pressure increasing above atmospheric pressure increase in the curvature (upward movement) of the diaphragm movement of the ribs closer together due to contraction of the internal intercostal muscles contraction of the abdominal muscles
flattening (downward movement) of the diaphragm
Physiological dead space is always less than anatomical dead space is the volume of air in the lung after a maximal inspiration includes alveolar units with abnormally low V/Q ratios is equal to tidal volume minus anatomical dead space includes alveolar units with abnormally high V/Q ratios
includes alveolar units with abnormally high V/Q ratios
Which of the following is a cause of asthma? loss of alveoli lack of pulmonary surfactant inflammation of the bronchioles environmental chemicals that stimulate beta-2 adrenergic receptors elevation of intrapleural pressure to equal atmospheric pressure
inflammation of the bronchioles
Under normal circumstances, which of the following would result from an increase in transpulmonary pressure? pneumothorax inhalation/inspiration emphysema a collapsed lung exhalation/expiration
inhalation/inspiration
What is found in between the visceral and parietal pleura? surfactant fluid alveolar membrane intrapleural fluid visceral pleura a large air space
intrapleural fluid
The time that is required for CO2 to reach equilibrium between alveolar air and pulmonary capillary blood is less than the time required for O2 to reach equilibrium between the alveolar air and pulmonary capillary blood equal to the time required for O2 to reach equilibrium between the alveolar air and pulmonary capillary blood greater than the time required for O2 to reach equilibrium between the alveolar air and pulmonary capillary blood
less than the time required for O2 to reach equilibrium between the alveolar air and pulmonary capillary blood
The stability of small alveoli is promoted by the properties of surfactant which lead to a ______ surface tension in small compared to larger alveoli. higher lower equivalent or equal
lower
Which of the following is NOT a function of the respiratory system? regulation of blood H+ concentration net uptake of carbon dioxide from the air and removal of oxygen from the blood defense against microbes trapping of blood clots phonation
net uptake of carbon dioxide from the air and removal of oxygen from the blood
A poison has led to the paralysis of both inspiratory and expiratory muscles. Which of the following class of drugs could include this poison? alpha adrenergic receptor antagonist beta adrenergic receptor antagonist muscarinic receptor antagonist nicotinic receptor antagonist
nicotinic receptor antagonist
What is the correct term for the outermost layer of the pleural membrane? basal membrane parietal pleura visceral pleura alveolar sac mediastinum
parietal pleura
What determines the net direction of net gas diffusion in the body? the solubility of the gas in blood partial pressure differences the size of the gas molecule pH temperature
partial pressure differences
Surfactant increases the surface tension of the liquid layer covering the surface of the alveolar wall is absent in adult lungs is secreted by epithelial cells in the bronchioles of the lung reduces surface tension of the liquid layer covering the surface of the alveolar wall
reduces surface tension of the liquid layer covering the surface of the alveolar wall
Which is a result of hyperventilation? metabolic alkalosis respiratory acidosis metabolic acidosis respiratory alkalosis increased blood PCO2
respiratory alkalosis
Which structure is NOT part of the "anatomical dead space?" terminal bronchiole bronchiole bronchus respiratory bronchiole trachea
respiratory bronchiole
Which of the following structures in the lung would be considered part of the respiratory zone of the lung? trachea respiratory bronchioles tertiary bronchi terminal bronchioles
respiratory bronchioles
During exercise, blood in the capillaries of the exercising muscle is warmed, PCO2 is elevated and pH is lowered. shift the oxygen dissociation curve to the left and increase the Hb saturation of the blood at a PO2 of 40 Torr shift the oxygen dissociation curve to the left and reduce the Hb saturation of the blood at a PO2 of 40 Torr shift the oxygen dissociation curve to the right and reduce the Hb saturation of the blood at a PO2 of 40 Torr shift the oxygen dissociation curve to the right and increase the Hb saturation of the blood at a PO2 of 40 Torr
shift the oxygen dissociation curve to the right and reduce the Hb saturation of the blood at a PO2 of 40 Torr
The volume of air flowing into the alveoli during inhalation/inspiration is increased when there is an increase in which of these? the pressure gradient from the atmosphere to the alveoli airway resistance the pressure in the intrapleural space the curvature of the diaphragm the volume of air in the intrapleural space
the pressure gradient from the atmosphere to the alveoli
The volume of air flowing into the alveoli during inhalation/inspiration is increased when there is an increase in which of these? the volume of air in the intrapleural space the pressure in the intrapleural space airway resistance the curvature of the diaphragm the pressure gradient from the atmosphere to the alveoli
the pressure gradient from the atmosphere to the alveoli
Which of the following is most responsible for keeping the lung surface and the thoracic wall from separating? the surface tension of the intrapleural fluid the negative pressure in the alveolar space alveolar pressure is higher than atmospheric pressure the presence of surfactant the force exerted by the external intercostal muscles
the surface tension of the intrapleural fluid
Which of the following conditions would result in a systemic arterial PO2 lower than is typical of a healthy person at sea level? breathing 100% oxygen breathing regular air in a hyperbaric chamber (higher that normal atmospheric pressure) having iron-deficiency anemia maintaining alveolar ventilation constant while decreasing metabolic rate traveling to high altitude
traveling to high altitude
What is the term used to describe the layer of the pleural membrane attached to the surface of the lung? parietal pleura visceral pleura alveolar sac thoracic pleura basal membrane
visceral pleura