Human gas exchange system: structure and function

• What are the main structures in the upper respiratory tract?

  • Nose
  • Nasal cavity
  • Nasal conchae
  • Frontal sinus
  • Sphenoidal sinus
  • Pharynx
  • Larynx
• What structure is between the nose and trachea?

  Larynx
• What are the two main sections of the respiratory system?

  Upper Tract and Lower Tract
• What is the function of the nasal cavity in the respiratory system?

  It allows air to enter the respiratory system
• What is the function of the nasal conchae?

  To warm and moisten air
• Which respiratory structure connects the nasal cavity to the trachea?

  Pharynx
• What is the name of the major muscle involved in breathing, located at the bottom of the chest cavity?

  Diaphragm
• How do the components of the Upper Tract differ from those of the Lower Tract?

  Upper Tract includes nasal cavity and pharynx
• What is the first structure air passes through after the pharynx?

  Trachea
• What are the names of the main bronchi that branch off from the trachea?

  • Right superior lobe bronchus
  • Left superior lobe bronchus
  • Right and left main bronchi
• Into how many main bronchi does the trachea branch?

  Two main bronchi
• What is the role of cartilage rings in the trachea?

  They maintain airway stability
• How do the bronchi further divide within the lungs?

  • The main bronchi divide into smaller bronchi (B1-B10) that branch out to the different lobes of the lungs.
• What is the name of the cartilage that forms the Adam's apple?

  Thyroid cartilage
• What structure connects the pharynx to the lungs?

  Trachea
• What are the alveoli?

  Tiny air sacs at the end of bronchioles
• What is the relationship between bronchi and bronchioles?

  Bronchi branch into bronchioles
• Which part of the respiratory system facilitates gas exchange in the lungs?

  Alveoli
• How does the alveoli facilitate the exchange of gases in the lungs?

  Alveoli allow for the diffusion of oxygen and carbon dioxide between the air and blood
• What is the name of the ligament that connects the cricoid and arytenoid cartilages?

  Arytenoid (intercartilagenous) ligaments
• What is the primary action of the ribs during expiration?

  They move down and in
• What do the bronchi further divide into?

  Progressively smaller bronchioles
• What happens to the ribs during inspiration?

  They move up and out
• What supports the structure of the trachea?

  C-shaped cartilage rings
• What happens to the diaphragm during expiration?

  It relaxes and moves upward
• What is the overall purpose of the breathing mechanism?

  To facilitate gas exchange
• What occurs during expiration in terms of chest contraction?

  Chest contracts, raising pressure
• What is the primary function of the alveoli?

  Gas exchange occurs in the alveoli
• How does chest volume change during inspiration?

  It expands
• What is the effect of increased chest cavity volume on lung pressure during inspiration?

  It causes lung pressure to decrease
• What is the function of the mucosa in the trachea and bronchi?

  • Traps dust and pathogens
  • Protects the respiratory tract
  • Keeps airways clear
• What is the primary function of the diaphragm in breathing?

  To change chest cavity volume
• Which sinus is located above the nasal conchae?

  Frontal sinus
• How does the movement of air and blood occur in the alveoli?

  • Air moves in and out of the alveoli
  • Blood from the pulmonary artery is deoxygenated
  • Oxygen diffuses from the alveoli into the blood
  • Carbon dioxide diffuses from the blood into the alveoli
• What gas diffuses from capillaries to alveoli?

  Carbon dioxide
• What is the formula for the bicarbonate buffer system in red blood cells?

  HCO3- + H+ ⇌ H2CO3 ⇌ CO2 + H2O
• What are the key events that occur during the breathing cycle?

  • Inhalation: Chest expands, diaphragm contracts, air drawn into lungs
  • Exhalation: Chest contracts, diaphragm relaxes, air expelled from lungs
• What are the components of the alveoli?

  • Capillary wall
  • One cell thick
  • Red blood cells
  • Deoxygenated and oxygenated blood
• What is the pressure change during expiration?

  Pressure increases
• What is the function of the alveoli in the lungs?

  Movement of air