Respiratory System


Respiratory System

You should be able to:
  • Describe the adaptation of structure to function along the respiratory tract.
  • Describe the path of air into (O2) and out of (CO2) the respiratory system.
  • Describe the histology throughout the path of air.
  • Distinguish the histological components of the respiratory tree at all levels.
  • Recognise and describe the bronchi and bronchioles.
  • Describe the histological organisation of the alveolar wall (blood-air barrier with its cellular and structural components) and how it is adapted to its function.
  • Describe the morphology and function of specialised cells in the respiratory system.
  • List the structures of the respiratory system and function of each part.

Slides for this week

For each slide, complete the work as listed below. Completing the whole slide will assist you in understanding and retention. For each slide, allocate an A3 spread in your workbook. Remember to add the slide and its page number to the index in the front of the book.


  • Study the supplied diagrams and slides (see the Respiratory System on HistoWeb). Annotate each. Where possible, give the function of each labelled structure or cell.
  • What epithelium lines the upper airways?
  • Name the cells that constitute olfactory epithelium.
  • Name the cell types that make up the epithelium lining of the bronchial tree.
  • Name the three cell types present in the alveolar epithelium and their function.
  • What happens to air in the conducting part of the respiratory system?
  • Describe the histology where gas exchange takes place between the blood and air.
  • How does the epithelium change from the nose to the alveolus?
  • How does some common diseases affect the histological structure of the respiratory system?
  • How does this affect the functioning of the respiratory system? Be specific.
  • Compare and contrast the functions of upper respiratory tract with the lower respiratory tract.
  • Describe the path of oxygen from outside the body until it takes part in a metabolic process, and the corresponding reverse path followed by carbon dioxide.
  • Make an annotated diagram of the complete respiratory system, indicating the function of each part.
  • Describe the histology seen in a cross-section for each of the following passages of the respiratory system:
    1. Nasal cavities
    2. Trachea
    3. Bronchioles
    4. Respiratory bronchioles
    5. Alveolar duct
    6. Alveoli
  • List the functions of each part of the respiratory system.
  • Name the cells present in each part of the respiratory system and the function of each.
  • Make an annotated diagram of the blood-air barrier, clearly indicating the components and surrounding cells and tissues.
  • Correlate each of the described histological structures with its corresponding view on a microscopic slide.
  • Complete the tasks for each slides in the practical workbook or your portfolio book.
  • Dry air consist of 78% nitrogen, 21% oxygen, and 1% argon, carbon dioxide, and other gases. Air also contains a variable amount of water vapour. Gas exchange by diffusion in the alveoli within the lungs changes these proportions. The composition of inhaled and exhaled air is different.
    1. How much oxygen is absorbed by the lungs?
    2. What happens with nitrogen?
    3. Carbon monoxide is toxic on inhalation. Nitrogen is not. Describe the two mechanisms at work.
  • Compare and contrast the conducting and respiratory zones.
  • Complete the following:

    Inhaled air contains: more ______ used to create _____ and
    less _____ than...
    Exhaled air which contains:
    more _____ produced as a waste product of _____ and
    less _____ as it has been used in _____.

  • Complete the following table:
Component Epithelium Secretory Cell Cartilage Smooth Muscle Glands in CT Diameter Other
Bronchioles to Terminal Bronchioles
Respiratory Bronchioles
Alveolar Duct

© augustus 2020 marius loots