Y1S1 012 III Physiology Respiratory System Pressures
30 Questions
4 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the approximate pressure within the pleural cavity when the glottis is open?

  • 0 mm Hg
  • -2 mm Hg
  • 760 mm Hg
  • -4 mm Hg (correct)

    • According to Boyle's Law, what is the relationship between the pressure and volume of a gas in a system?

  • Constantly proportional
  • Directly proportional
  • Not related
  • Inversely proportional (correct)

    • What is the percentage of oxygen in the atmosphere?

  • 20.95% (correct)
  • 78.09%
  • 0.93%
  • 0.039%

    • During the Valsalva manoeuvre, what happens to the intrathoracic and intrapleural pressures?

    <p>They increase</p> Signup and view all the answers

    What is the relationship between changes in lung volume and intrapulmonary pressure?

    <p>Inversely proportional</p> Signup and view all the answers

    What is the pressure within the thoracic cavity approximated to?

    <p>Intrapleural pressure</p> Signup and view all the answers

    What is the relationship between the volume of gas crossing the alveolar-capillary barrier and the pressure difference between the two surfaces?

    <p>Directly proportional to the pressure difference</p> Signup and view all the answers

    What is the effect of high O2 administration on diffusion capacity?

    <p>It increases the diffusion capacity</p> Signup and view all the answers

    What is the primary reason why CO is used as a diffusion capacity estimator?

    <p>It is highly soluble in the alveolar-capillary membrane</p> Signup and view all the answers

    What is the result of an increase in hydrogen ions in the blood?

    <p>A decrease in pH</p> Signup and view all the answers

    Which of the following pulmonary diseases is caused by a bacillus bacterium?

    <p>Tuberculosis</p> Signup and view all the answers

    What is the effect of diseases that calcify lung parenchyma on the diffusion of gases?

    <p>They decrease the surface area of the respiratory surfaces</p> Signup and view all the answers

    What is the primary mechanism by which respiratory membranes are cleared of CO?

    <p>Mechanisms that lower the partial pressure of CO</p> Signup and view all the answers

    What is the primary effect of fibrous connective tissue buildup in lungs during pulmonary fibrosis?

    <p>Reduced elasticity of lungs</p> Signup and view all the answers

    How many phases are involved in gas transport and exchange in terrestrial vertebrates?

    <p>4</p> Signup and view all the answers

    Which of the following is NOT a characteristic of emphysema?

    <p>Increased oxygen diffusion</p> Signup and view all the answers

    What is the primary cause of inflammation in bronchitis?

    <p>Infectious pathogens</p> Signup and view all the answers

    What is the percentage of lung cancers caused by smoking?

    <p>Almost 90%</p> Signup and view all the answers

    What is the primary form of oxygen in arterial blood?

    <p>Oxygen bound to heme group</p> Signup and view all the answers

    What is the effect of high affinity binding of oxygen to haemoglobin?

    <p>Increase in oxygen binding to subsequent heme groups</p> Signup and view all the answers

    What is the approximate percentage of oxygen transported in dissolved state in blood at 95 mmHg?

    <p>3.3%</p> Signup and view all the answers

    What is the effect of CO poisoning on oxygen transport in blood?

    <p>Decrease in oxygen binding to haemoglobin</p> Signup and view all the answers

    What is the significance of the oxygen-haemoglobin dissociation curve?

    <p>It describes the relationship between oxygen saturation and partial pressure of oxygen</p> Signup and view all the answers

    What is the purpose of a hyperbaric chamber in oxygen therapy?

    <p>To increase oxygen saturation at high atmospheric pressure</p> Signup and view all the answers

    What percentage of the total surface area of the alveoli is comprised of Type I cells?

    <p>Approximately 95%</p> Signup and view all the answers

    What is the primary function of Type II cells in the alveoli?

    <p>Secretion of surfactant</p> Signup and view all the answers

    What is the result of increased surface tension in the alveoli?

    <p>Decreased lung inflation</p> Signup and view all the answers

    What is the relationship between alveolar radius and surfactant efficacy?

    <p>Alveolar radius is inversely related to surfactant efficacy</p> Signup and view all the answers

    What is the primary mechanism by which surfactant reduces surface tension in the alveoli?

    <p>By becoming interspersed between water molecules and disrupting intermolecular cohesion</p> Signup and view all the answers

    What is the result of the Law of Laplace on the alveoli?

    <p>Increased surface tension in smaller alveoli</p> Signup and view all the answers

    Study Notes

    Pleural Cavity Pressure

    • The pleural cavity pressure is approximately -4 mmHg when the glottis is open.

    Boyle's Law

    • Boyle's Law states that the pressure and volume of a gas in a closed system are inversely proportional to each other. This means that if the volume increases, the pressure decreases, and vice versa.

    Atmospheric Oxygen

    • The percentage of oxygen in the atmosphere is approximately 21%.

    Valsalva Manoeuvre

    • During the Valsalva manoeuvre, both intrathoracic and intrapleural pressures increase.

    Lung Volume and Intrapulmonary Pressure

    • Changes in lung volume are directly related to intrapulmonary pressure. Increased lung volume results in decreased intrapulmonary pressure, and vice versa.

    Thoracic Cavity Pressure

    • The pressure within the thoracic cavity is approximated to -4 mmHg.

    Alveolar-Capillary Barrier Gas Exchange

    • The volume of gas crossing the alveolar-capillary barrier is directly proportional to the pressure difference between the two surfaces.

    High O2 and Diffusion Capacity

    • High O2 administration has minimal effect on diffusion capacity.

    CO as Diffusion Capacity Estimator

    • CO is used as a diffusion capacity estimator because it binds to haemoglobin with very high affinity, permitting measurement of gas transfer across the alveolar-capillary membrane.

    Increased Hydrogen Ions

    • An increase in hydrogen ions in the blood results in acidosis, which can lead to respiratory distress.

    Bacillus-Caused Pulmonary Disease

    • Tuberculosis is a pulmonary disease caused by a bacillus bacterium (Mycobacterium tuberculosis).

    Calcification and Gas Diffusion

    • Diseases that calcify lung parenchyma, such as silicosis, significantly decrease gas diffusion due to the rigid, inflexible nature of the calcified tissue.

    CO Removal From Respiratory Membranes

    • Carbon monoxide (CO) is primarily cleared from respiratory membranes through diffusion into the bloodstream and subsequent binding to haemoglobin.

    Pulmonary Fibrosis Effects

    • Fibrous connective tissue buildup in lungs during pulmonary fibrosis impairs gas exchange and reduces lung compliance, leading to a restrictive lung disease.

    Gas Transport Phases

    • There are four phases involved in gas transport and exchange in terrestrial vertebrates:
      • Pulmonary ventilation (breathing)
      • Gas diffusion across the alveolar-capillary membrane
      • Gas transport in blood
      • Gas diffusion between blood and cells

    Emphysema Characteristics

    • Emphysema is characterized by:
      • Abnormal permanent enlargement of airspaces distal to terminal bronchioles
      • Destruction of alveolar walls
      • Reduction in elastic recoil
      • Air trapping
      • Dyspnea

    Bronchitis Inflammation

    • The primary cause of inflammation in bronchitis is irritation and infection of the airways by viruses, bacteria, or other irritants.

    Smoking and Lung Cancer

    • 80-90% of lung cancers are caused by smoking.

    Oxygen in Arterial Blood

    • The primary form of oxygen in arterial blood is bound to haemoglobin.

    High Affinity Oxygen Binding

    • High affinity binding of oxygen to haemoglobin ensures efficient oxygen transport in the blood.

    Dissolved Oxygen in Blood

    • The percentage of oxygen transported in a dissolved state in blood at 95 mmHg is approximately 1.5%.

    CO Poisoning and Oxygen Transport

    • CO poisoning reduces oxygen transport because CO binds to haemoglobin with much higher affinity than oxygen.

    Oxygen-Haemoglobin Dissociation Curve Significance

    • The oxygen-haemoglobin dissociation curve depicts the relationship between oxygen saturation of haemoglobin and partial pressure of oxygen in the blood. It demonstrates the factors that can shift this curve, such as pH, temperature, 2,3-DPG, and CO2 levels.

    Hyperbaric Chamber in Oxygen Therapy

    • A hyperbaric chamber used in oxygen therapy is a sealed environment that increases atmospheric pressure to deliver higher concentrations of oxygen to tissues.

    Alveoli Surface Area - Type I Cells

    • Type I cells comprise approximately 95% of the total surface area of the alveoli.

    Type II Cells Function

    • Type II cells in the alveoli are responsible for producing surfactant.

    Increased Alveolar Surface Tension

    • Increased surface tension in the alveoli can lead to alveolar collapse.

    Surfactant Efficacy and Alveolar Radius

    • Surfactant efficacy is more pronounced in small alveoli, preventing their collapse due to the Laplace law effect.

    Surfactant Surface Tension Reduction

    • Surfactant reduces surface tension in the alveoli by decreasing the cohesive forces between water molecules.

    Law of Laplace and Alveoli

    • The Law of Laplace states that pressure within a sphere is directly proportional to surface tension and inversely proportional to radius. This means that smaller alveoli have a higher tendency to collapse due to higher pressure unless surfactant is present.

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Related Documents

    PHYL1010 012 Respiratory System PDF

    Description

    Test your understanding of the different pressures involved in the respiratory system, including airway pressure, intra-alveolar pressure, and intrapleural pressure. Learn how these pressures work together to facilitate breathing and gas exchange.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser