Pulmonary System Function
15 Questions
0 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

Which type of alveolar cell is responsible for producing surfactant to lower surface tension and facilitate gas exchange?

  • Type I alveolar cells
  • Alveolar macrophages
  • Type III alveolar cells
  • Type II alveolar cells (correct)

    • What physiological process is directly initiated by cough receptors located in the carina?

  • Forceful expulsion of air to clear the airway (correct)
  • Bronchodilation to improve airflow
  • Increased mucus production
  • Activation of alveolar macrophages

    • What is the primary function of the mucociliary clearance mechanism in the respiratory system?

  • To regulate the diameter of the bronchioles
  • To humidify inhaled air before it reaches the alveoli
  • To trap and remove foreign particles and mucus from the airways (correct)
  • To facilitate gas exchange in the alveoli

    • Which of the following factors would directly lead to an increase in airway resistance?

    <p>Presence of mucus in the airways (C)</p> Signup and view all the answers

    What is the primary role of peripheral chemoreceptors in the control of ventilation?

    <p>Sensing changes in arterial oxygen, carbon dioxide, and pH levels (D)</p> Signup and view all the answers

    What causes air to passively exit the lungs during normal expiration?

    <p>Elastic recoil of the lungs (B)</p> Signup and view all the answers

    Which event directly results from capillary hydrostatic pressure exceeding colloid osmotic pressure in pulmonary circulation?

    <p>Fluid movement from capillaries to the interstitial space (D)</p> Signup and view all the answers

    Which of the following accurately describes the role of Type II alveolar cells?

    <p>They produce surfactant, which decreases surface tension within the alveoli, promoting efficient gas exchange. (D)</p> Signup and view all the answers

    The cough reflex is triggered by receptors located in the carina. What is the primary physiological purpose of this reflex?

    <p>To initiate a high-pressure expulsion of air to clear the airway of irritants and foreign material. (B)</p> Signup and view all the answers

    Which of the following best describes the function of the mucociliary transport system?

    <p>To trap particles and pathogens, then propel them upwards to be swallowed or expectorated. (B)</p> Signup and view all the answers

    What effect does stimulation of β2-adrenergic receptors have on the respiratory system?

    <p>Bronchodilation and increased respiratory rate. (D)</p> Signup and view all the answers

    How would a reduction in airway diameter affect airway resistance and the work of breathing?

    <p>Increased airway resistance, increased work of breathing. (C)</p> Signup and view all the answers

    How do baroreceptors influence ventilation when blood pressure increases?

    <p>They inhibit inspiration, leading to a decreased rate of ventilation. (D)</p> Signup and view all the answers

    What is the anticipated effect on alveolar gas exchange when capillary hydrostatic pressure exceeds colloid osmotic pressure in the pulmonary circulation?

    <p>Poor gas exchange due to alveolar edema. (D)</p> Signup and view all the answers

    What causes air to enter the lungs during normal inspiration?

    <p>Negative intrapleural pressure created by the chest wall muscles contracting and the diaphragm moving downward. (B)</p> Signup and view all the answers

    Flashcards

    Mucociliary Clearance

    A defense mechanism in the respiratory tract involving cilia and mucus to trap and sweep away foreign particles.

    Cough Reflex

    A protective mechanism initiated by cough receptors in the carina to clear airways of foreign matter.

    Type I Alveolar Cells

    Epithelial cells that form the structure of alveoli, facilitating gas exchange.

    Type II Alveolar Cells

    Cells that produce surfactant to lower surface tension in alveoli for better gas exchange.

    Signup and view all the flashcards

    Pulmonary Edema

    Fluid accumulation in alveoli due to pressure imbalances, leading to poor gas exchange.

    Signup and view all the flashcards

    Airway Resistance

    Resistance encountered in the respiratory pathways, influenced by diameter and gas flow patterns.

    Signup and view all the flashcards

    Autonomic Nervous System Control

    Controls bronchoconstriction and bronchodilation via sympathetic and parasympathetic stimulation.

    Signup and view all the flashcards

    Baroreceptors

    Sensors in the aortic arch and carotid bodies that respond to blood pressure changes affecting breathing.

    Signup and view all the flashcards

    Mucus Production

    The creation of mucus by goblet cells and glands in the trachea and bronchi.

    Signup and view all the flashcards

    Alveolar Macrophages

    Immune cells in the alveoli that phagocytize foreign particles.

    Signup and view all the flashcards

    Ventilation

    The process of air moving in and out of the lungs.

    Signup and view all the flashcards

    Perfusion

    The blood flow to alveoli for gas exchange.

    Signup and view all the flashcards

    Expiration Mechanism

    Lungs deflate passively during breathing out.

    Signup and view all the flashcards

    Inspiration Mechanism

    Chest wall muscles contract, lowering diaphragm to draw air in.

    Signup and view all the flashcards

    Cough Receptors

    Receptors located at the carina that trigger a cough reflex.

    Signup and view all the flashcards

    Pulmonary Circulation Mechanism

    Fluid movement from capillaries to interstitial space due to pressure imbalance.

    Signup and view all the flashcards

    Study Notes

    Pulmonary System Function

    • The pulmonary system is responsible for gas exchange.
    • Airway structures include the trachea, bronchi, bronchioles, and alveoli. The trachea bifurcates into two primary bronchi at the carina.
    • The lungs are enclosed by the pleura, with parietal pleura lining the chest cavity and visceral pleura surrounding the lungs.
    • Alveoli are tiny air sacs where gas exchange takes place. Alveolar sacs are clusters of alveoli.
    • Pulmonary capillaries surround alveoli for efficient gas exchange.

    Mucociliary Clearance

    • The respiratory tract's lining contains ciliated columnar epithelium and goblet cells.
    • Cilia move mucus upwards, enabling the elimination of foreign particles and microorganisms.
    • Goblet cells produce mucus, which entraps foreign substances.
    • Mucus-producing glands contribute to this process.

    Cough Reflex

    • The cough reflex is a force/pressure mechanism to clear foreign matter from the airways.
    • Cough receptors are located in the carina, the point where the trachea branches into the two primary bronchi.

    Alveolar Cells

    • Alveolar cells (Type I and II) are involved in gas exchange and surfactant production.
    • Type I cells are epithelial structure cells.
    • Type II cells produce surfactant.
    • Surfactant lowers surface tension in alveoli, facilitating gas exchange. Surfactant is damaged by smoking and silica.
    • Alveolar macrophages phagocytize foreign particles.

    Mechanisms Affecting Pulmonary Circulation

    • Capillary hydrostatic pressure exceeding colloid osmotic pressure can cause fluid leakage into the interstitial space.
    • This can lead to alveolar edema, impacting gas exchange. Fluid accumulating into the alveoli is a primary result of poor gas exchange.

    Ventilation and Perfusion

    • Ventilation and perfusion are two processes significantly influencing alveolar respiration.

    Airway Resistance

    • Airway resistance is impacted by airway diameter.
    • Factors affecting airway resistance include mucus, bronchospasm, stress, pulmonary conditioning, and age. A decrease in airway diameter will result in a greater airway resistance.

    Expiration Mechanism

    • The lungs deflate passively during exhalation.
    • Functional residual capacity refers to the amount of air remaining in the lungs after passive exhalation.

    Inspiration Mechanism

    • The inspiratory process involves chest wall muscle contraction, diaphragm movement, and intrapleural pressure changes. Inspiration creates a negative intrapleural pressure to inflate the lungs.

    Ventilation Control

    • The autonomic nervous system regulates respiratory rate (RR).
    • Parasympathetic stimulation via the vagus nerve, releasing acetylcholine, causes bronchoconstriction and reduced RR.
    • Sympathetic stimulation, activating β₂-adrenergic receptors, relaxes muscles, leading to bronchodilation and increased RR.

    Neurologic Control of Ventilation

    • The respiratory center in the brainstem, pneumotaxic center, central chemoreceptors, peripheral chemoreceptors, baroreceptors, and proprioceptors are elements of ventilation control.

    Baroreceptors and Peripheral Chemoreceptors

    • Baroreceptors, located in aortic arch and carotid bodies, respond to blood pressure (BP) fluctuations.
    • High BP inhibits inspiration, while low systolic BP (<80 mm Hg) stimulates inspiration.
    • Peripheral chemoreceptors in the aortic arch and carotid bodies, monitor arterial oxygen (O₂), hydrogen ion (H⁺) concentration (pH), and carbon dioxide (CO₂) levels.

    Perfusion

    • Pulmonary vasculature is a low-pressure system.
    • Capillary beds surround alveoli, enabling efficient gas exchange.

    Hypoxic Vasoconstriction

    • Alveolar hypoxia triggers vasoconstriction, diverting blood flow from poorly ventilated areas to better-ventilated areas of the lungs.

    Gas Exchange in Alveoli

    • Efficient gas exchange between the air in the alveoli and the blood in pulmonary capillaries is essential for respiration in alveoli.
    • Oxygen (O₂) diffuses into the blood, and carbon dioxide (CO₂) diffuses out of the blood.

    Six Barriers

    • Six structures participate in the passage of gases across the respiratory membrane. These include red blood cells, plasma, capillary membrane, interstitial fluid, alveolar membrane, and surfactant.

    Studying That Suits You

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

    Quiz Team

    Related Documents

    Pulmonary System Function PDF

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser