lecture 8

• What is the purpose of the Module Evaluation Survey?

  To gather feedback for student experience improvement
• Who is the lecturer for Respiration I?

  1. Andrew Cobb
• What are the learning objectives of the Respiration I module?

  To understand respiration processes and anatomy
• What is the primary function of the respiratory system?

  Supply oxygen and dispose of carbon dioxide
• What is required for respiration to occur effectively?

  A properly functioning circulatory system
• What are the four processes of respiration?

  1. Pulmonary ventilation (breathing)
  2. External respiration
  3. Transport of respiratory gases
  4. Internal respiration
• What does pulmonary ventilation consist of?

  Inspiration and expiration
• What occurs during external respiration?

  O$_2$ diffuses into blood, CO$_2$ diffuses into lungs
• How does the cardiovascular system relate to respiration?

  It transports O$_2$ and CO$_2$ in blood
• What are the main components of the lower respiratory system?

  Larynx, trachea, bronchi, and lungs
• What are the functions of the nose in the upper respiratory system?

  • Provides an airway
  • Warms and moistens air
  • Filters and cleans air
  • Contains olfactory senses
• What type of epithelium lines the respiratory mucosa?

  Pseudostratified ciliated columnar epithelium
• What do seromucous glands and goblet cells secrete?

  Mucous containing antimicrobial enzymes
• What is the role of cilia in the respiratory mucosa?

  Move mucous towards the throat
• What are the three sections of the pharynx?

  Nasopharynx, oropharynx, laryngopharynx
• What is the primary function of the larynx?

  Maintain an open airway and voice production
• How many cartilages compose the larynx?

  Nine cartilages
• What is the function of the epiglottis?

  Prevent food from entering the trachea
• What does the trachea allow during respiration?

  Passage of air
• What is the structure of the trachea's mucosa?

  Goblet cell-containing pseudostratified epithelium
• What happens to the trachea during respiration?

  It moves due to its elasticity
• Describe the bronchial tree structure.

  • Trachea divides into 2 bronchi
  • Bronchi branch ~23 times
  • Main bronchi divide into secondary (lobar) bronchi
  • Secondary bronchi divide into segmental (tertiary) bronchi
  • Smallest branches are bronchioles
• What contributes to airway resistance in the respiratory system?

  Narrowing of airways due to bronchoconstriction
• What is the diameter of medium-sized bronchi?

  2-5 mm
• What is the respiratory zone and its components?

  • Begins at respiratory bronchioles
  • Contains alveolar ducts
  • Leads to alveoli for gas exchange
  • Alveoli arranged in clusters (alveolar sacs)
• How many alveoli are there in the lungs?

  Around 300 million
• What is the structure of the respiratory membrane?

  Single layer of squamous epithelial cells
• What do type 2 alveolar cells secrete?

  A surfactant that protects alveolar surfaces
• How does gas exchange occur in the respiratory membrane?

  By simple diffusion across the membrane
• What is the function of the lungs in respiration?

  • Composed mainly of air spaces
  • Elastic connective tissue aids respiration
  • Deoxygenated blood supplied via pulmonary arteries
  • Oxygenated blood leaves via pulmonary veins
  • Diaphragm is the main muscle for breathing
• What happens to the thoracic cavity during inspiration?

  Volume increases, causing pressure to drop
• What is the primary mechanism of expiration?

  Passive process due to lung elasticity
• What is the role of the diaphragm during breathing?

  Contracts to pull air into the lungs
• What are the changes in pulmonary pressure during breathing?

  • Pressure drops during inspiration
  • Pressure rises during expiration
  • Pleural cavity surrounds lungs
• What is a spirometer used for?

  Measuring lung function
• Who are the authors of the referenced textbooks?

  Elaine Nicpon Marieb and Katja Hoehn
• What is the title of the referenced textbook by Tortora?

  Principles of Anatomy and Physiology
• Why is the respiratory system important for homeostasis?

  It regulates oxygen and carbon dioxide levels
• How does the diaphragm regulate breathing?

  By contracting and relaxing to change volume
• Why is the alveolar surface area significant for gas exchange?

  It maximizes the area for diffusion