Mechanism of Breathing

• What is the purpose of the alveoli in the respiratory system?

  For gas exchange
• How does the structure of the respiratory tract facilitate gas exchange?

  It ends in alveoli, maximizing surface area
• What are the two main branches of the trachea that enter the lungs?

  Bronchus
• What structure is the first part of the respiratory system?

  Nasal cavity
• What is the function of the pleural cavity and fluid?

  • Reduces friction between the lungs and chest wall during breathing
  • Creates a pressure gradient that helps the lungs inflate and deflate
• What is the name of the large, flat muscle at the bottom of the chest cavity that helps with breathing?

  Diaphragm
• What happens to the pressure inside the lungs during exhalation?

  It increases
• What are the key terms related to lung capacity and tidal volume?

  • Tidal volume: 0.5L (normal breath)
  • Lung capacity: Up to 6L (max breath)
• What does the image in the study material illustrate about tidal volume?

  It shows the natural breathing pattern
• What happens to the thoracic cavity during inspiration?

  The thoracic cavity expands
• What happens to air after it passes through the trachea?

  It branches into larger bronchi
• What do the intercostal muscles do during inhalation?

  They contract to expand the chest cavity
• What is the result of the coordinated movements of the diaphragm and intercostal muscles?

  They change lung pressure and drive air in and out
• What happens to air during inhalation due to lower pressure in the lungs?

  Air is pulled into the alveoli
• What happens to the diaphragm during inhalation?

  It contracts downwards
• What is the function of the bronchioles?

  The bronchioles are small airways that connect the bronchi to the alveoli, allowing air to flow in and out of the lungs.
• What is the name of the cavity that contains fluid and surrounds the lungs?

  Pleural cavity
• What is the result of increased pressure inside the lungs?

  Air pushes out through the respiratory tract
• How does tidal volume contribute to overall breathing patterns?

  It represents regular air movement during breathing
• What are the key differences between inhalation and exhalation?

  • Inhalation:
  • Chest expands
  • Diaphragm contracts
  • Intercostal muscles contract
  • Pressure decreases
  • Air in
  • Exhalation:
  • Chest contracts
  • Diaphragm relaxes
  • Intercostal muscles relax
  • Pressure increases
  • Air out
• What visual representation is used to explain tidal volume?

  A regular wave between two volumes
• If air is blocked from entering the nasal cavity, what is the first structure it would reach?

  Trachea
• What is the name of the structure labeled "trachea"?

  The trachea is the airway that connects the larynx to the lungs.
• Which muscles are located between the ribs?

  Intercostal muscles
• How does lung capacity differ from tidal volume?

  Lung capacity includes reserve air, tidal volume does not
• How does the contraction of the chest cavity affect the lungs?

  It squeezes the lungs
• What do larger bronchi branch into?

  Smaller bronchioles
• What is the name of the structure labeled "diaphragm"?

  The diaphragm is a dome-shaped muscle that separates the thoracic and abdominal cavities.
• What are the key changes in the thoracic cavity, external intercostal muscles, and diaphragm during the inspiration and expiration processes?

  • During inspiration:
  • Thoracic cavity expands
  • External intercostal muscles contract
  • Diaphragm contracts
  • During expiration:
  • Thoracic cavity reduces
  • External intercostal muscles relax
  • Diaphragm relaxes
• If a patient has a blockage in their bronchioles, which respiratory structure would be most affected?

  The alveoli would be most affected by a blockage in the bronchioles.
• How do the diaphragm and intercostal muscles work together?

  They control breathing
• What are the key steps in the breathing process?

  • Inhalation: Chest expands, diaphragm contracts, air enters lungs
  • Exhalation: Chest contracts, diaphragm relaxes, air exits lungs
• If a person's vital capacity is $4.5 \text{ L}$, what is their residual volume if their functional residual capacity is $2.0 \text{ L}$?


  $1.5 \text{ L}$
• Where is the diaphragm located?

  Below the lungs
• What shape is the diaphragm muscle?

  Dome-shaped
• What are the key differences between breathing and respiration?

  • Breathing: Inhaling and exhaling air
  • Respiration: Using oxygen to release energy from food
  • Breathing is a part of respiration
• Why is the regulation of breathing important?

  It ensures the body has enough oxygen
• What happens when carbon dioxide increases in the blood?

  Breathing speeds up to remove excess CO2
• What is the name of the structure labeled "nasal turbinate"?

  The nasal turbinate is a structure in the nose.
• What happens to the thoracic cavity during expiration?

  The thoracic cavity reduces