MOD 5 - RESPIRATORY SYSTEM

• What is the role of wearing a mask during the COVID-19 pandemic?

  It is both protective and preventive
• What are the three public health advisories mentioned?

  Mask wearing, social distancing, hand washing
• What should you consider when exercising while wearing a mask?

  The physiologic effects and risks involved
• What are the physiologic effects of wearing a mask during exercise?

  It can restrict airflow and increase CO2 levels
• What is the first function of the respiratory system?

  Pulmonary ventilation
• What is external respiration?

  Gas exchange between alveoli and capillaries
• What is internal respiration?

  Gas exchange between circulation and cells
• What separates the upper and lower respiratory tracts?

  The glottis
• What are the components of the conducting portion of the respiratory system?

  • Nasal cavities
  • Nasopharynx
  • Larynx
  • Trachea
  • Bronchi
  • Bronchioles
  • Terminal bronchioles
• What is the function of the nasal cavity?

  To warm, moisten, and filter air
• What are vibrissae in the nasal cavity?

  Thick, short hairs that filter air
• What is epistaxis?

  A nosebleed
• Where is the olfactory epithelium located?

  At the roof of the nasal cavity
• What type of epithelium is the olfactory epithelium?

  Tall pseudostratified columnar epithelium
• What do olfactory cells do?

  Act as receptors for odor
• What are Bowman’s glands responsible for?

  Producing secretion for odor detection
• What are the main components of the nasopharynx?

  • Continuous with the oropharynx
  • Lined with respiratory epithelium
  • Contains mucous and serous glands
  • Contains lymphoid tissue (pharyngeal tonsil)
• What connects the pharynx with the trachea?

  The larynx
• What is the structure of the trachea?

  1. shaped hyaline cartilages with connective tissue
• What do ciliated cells in the trachea do?

  Move inhaled particles toward the mouth
• What are goblet cells responsible for?

  Secreting mucinogen to trap particles
• What is the diameter of primary bronchioles?

  1 mm or less
• What type of epithelium do terminal bronchioles have?

  Simple cuboidal epithelial lining
• What are the functions of Clara cells?

  • Divide and differentiate into ciliated cells
  • Secrete glycosaminoglycans
  • Metabolize airborne toxins
• What stimulates the division of cells to become alveolar cells?

  Increased toxic stress
• What is the function of the smooth muscle cells in the respiratory membrane?

  They wrap around the lumen in a spiraling arrangement
• What condition is marked by widespread contraction of smooth muscles in the bronchioles?

  Asthma
• What are the symptoms associated with asthma?

  Difficulty in expiration, mucus accumulation
• How do drugs that stimulate sympathetic activity help asthma patients?

  They cause smooth muscle relaxation
• What is the role of pulmonary surfactant?

  Reduces surface tension in alveoli
• What are the components of the respiratory portion of the lung?

  • Respiratory bronchioles
  • Alveolar ducts
  • Alveolar sacs
  • Alveoli
• What type of epithelium lines the respiratory bronchioles?

  Simple cuboidal epithelium
• What type of cells line the alveolar ducts?

  Type II pneumocytes and type I pneumocytes
• What is the function of alveolar ducts?

  They are linear passageways for gas exchange
• What are alveolar sacs?

  Expanded outpouchings of numerous alveoli
• What is the diameter of alveoli?

  About 200 µm
• What is the respiratory membrane also known as?

  Blood gas barrier
• How do interalveolar septa function in the respiratory system?

  They separate adjacent alveoli and contain pores
• What type of cells cover 95% of the alveolar surface?

  Type I pneumocytes
• What is the thickness of type I pneumocytes' cytoplasm?

  Less than 80 nm