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• What is the primary function of the respiratory system in animals?

  To filter air and facilitate gas exchange
• Why must the airways clear inhaled pathogens?

  To maintain homeostasis and prevent inflammation
• What are the two portions of the respiratory system?

  Conducting portion and respiratory portion
• What type of epithelium lines the majority of the respiratory tree?

  Pseudostratified columnar ciliated epithelium

  
• What type of epithelium lines the alveoli?

  Thin squamous epithelium
• What structures comprise the conducting portion of the respiratory system?

  • Nasal cavity
  • Trachea
  • Bronchi
  • Bronchioles

  
• What is the role of goblet cells in the conducting portion?

  To secrete mucus for pathogen defense
• How do cilia function in the respiratory system?

  They move mucus-bound particles for expulsion
• What supports the larger respiratory passages like the trachea?

  Hyaline cartilage rings

  
• What are the three major cell types found in the proximal airway?

  Ciliated, non-ciliated secretory, and basal cells
• How many cilia do ciliated cells typically have?

  200 to 300 cilia
• What characterizes the gas-exchange portion of the lung?

  • Composed of millions of alveoli
  • Lined by thin, simple squamous epithelium
  • Allows easy diffusion of gases
• What type of cells secrete surfactant in the alveoli?

  Type II pneumocytes

  
• What is the primary composition of surfactant?

  Dipalmitoyl phosphatidylcholine
• What is the function of Type I pneumocytes?

  Gas exchange and fluid transport

  
• How do Type II pneumocytes contribute to alveolar function?

  They secrete surfactant to prevent collapse

  
• What are the functions of the nasal cavity?

  • Modifies air for efficient gas exchange
  • Detects odors and transmits impulses to the brain
• What type of epithelium lines the nasal vestibule?

  Keratinized stratified squamous epithelium

  
• What are vibrissae in the nasal vestibule?

  Modified hairs that filter larger particles
• What epithelium transitions at the limen nasi?

  From keratinized stratified squamous to pseudostratified columnar
• What cell types are involved in olfaction?

  • Olfactory nerve cells
  • Sustentacular cells
  • Basal cells
• What do Bowman’s glands produce?

  Serous secretions to dissolve odors
• How do olfactory cilia function?

  They detect and transmit odors
• What type of neurons are olfactory nerve cells?

  Bipolar neurons
• Where do olfactory nerve fibers travel after detection?

  Through the cribriform plate of the ethmoid bone
• What do sustentacular cells do?

  Support olfactory nerve cells
• How are cell types distinguished in the olfactory epithelium?

  By the position and shape of their nuclei
• What is the epithelium of the pharynx like?

  • Changes with each pharyngeal segment
  • Nasopharynx: continuous with nasal cavity
  • Oropharynx and laryngopharynx: non-keratinized stratified squamous
• What is the role of lymphatic aggregates in the pharynx?

  Act as a first contact point for the immune system
• What is the function of the epiglottis?

  Prevents food from entering the airway
• What type of epithelium lines the lingual surface of the epiglottis?

  Stratified squamous non-keratinized epithelium

  
• What type of cartilage is found in the epiglottis?

  Elastic cartilage
• What is the laryngeal mucosa composed of?

  • Pseudostratified columnar ciliated epithelium
  • Seromucous glands
  • Goblet cells

  
• What type of epithelium covers the true vocal cords?

  Non-keratinized stratified squamous epithelium

  
• What is the function of the vocalis ligament?

  Attaches to the vocalis muscle
• What is the trachea's structure?

  Mucocartilaginous tube with smooth muscle
• What prevents the trachea from collapsing?

  Hyaline cartilage rings

  
• What is found in the adventitia of the trachea?

  • Adipocytes
  • Blood vessels
  • Nerves
• What type of epithelium lines the lumen of the trachea?

  Pseudostratified ciliated columnar epithelium

  
• What characterizes the bronchial tree?

  • Bifurcates into left and right primary bronchi
  • Supported by C-shaped rings of hyaline cartilage