Types of Respiratory System

8.1 Types of Respiratory System
 
Introduction
  • The ratio of total surface area to volume (TSA/V) depends on the size of the organism.
  • The bigger the size of the organism, the smaller the ratio of total surface area to volume.
  • This means that for large and complex organisms, the volume of the body that requires oxygen will increase more than its total surface area.
  • This explains why large and complex organisms cannot maintain gaseous exchange by diffusion through body surface only.
  • Large organisms require a special respiratory structure for the efficient exchange of gases.
 
Adaptations of Respiratory Structures For Efficient Exchange of Gases In Big Organisms
  • Large ratio of total surface area to volume (TSA/V) for the efficient exchange of respiratory gases.
  • A thin respiratory structure that is one cell thick, allows the diffusion of respiratory gases to occur.
  • The surface of the respiratory structure is always moist for respiratory gases to dissolve in them.
  • The respiratory structure is complete with a network of blood capillaries (except for insects), that allows for the efficient delivery of respiratory gases.
 
 
 
The Insect Respiratory Structure and Its Adaptations
  • There are small pores in the thorax and abdomen of insects called spiracles.
  • The spiracle allows the intake of air into the air tube system, which is the tracheal system.
  • The trachea branches out to form finer tubes called the tracheole.
  • Tracheole is the respiratory surface.
  • The tracheole has the following characteristics that allow for efficient respiratory gaseous exchange:
    • A large number of tracheoles provides a large total surface area for the exchange of gases.
    • The tracheole wall is thin and moist.
    • This allows oxygen gas to diffuse into the cells while carbon dioxide quickly diffuses out of the cells into the tracheole.
  • Some insects have air sacs in their trachea system.
  • This sac is filled with air to speed up the delivery of respiratory gas during active body movements.
  • The breathing system of insects is the tracheal system is as follows:
 
 
The Fish Respiratory Structure and Its Adaptations
  • The respiratory structure of fish is the gills.
  • The gills are made up of a line of filament that is supported by the gill arch.
  • The following characteristics of filament enable the rapid exchange of respiratory gases.
  • The filament has many thin and flat projections called lamella (plural: lamellae).
  • A large number of filaments and lamellae gives a large total surface area for an efficient gaseous exchange process.
  • The lamella membrane is thin and supplied with many blood capillaries for easy absorption and transport of oxygen and carbon dioxide.
 
 
The Frog Respiratory Structure and Its Adaptations
Skin
  • In an inactive state, the frog uses its skin for gaseous exchange. 
  • The skin is thin and highly permeable to respiratory gases.
  • The moist skin allows respiratory gases to dissolve in it.
  • Beneath the skin, there are many networks of blood capillaries to transport respiratory gases.
Lungs
  • The surface of the lungs is folded to increase the total surface area for the exchange of gases.
  • The thin lung membrane eases the diffusion of respiratory gases.
  • The moist lung walls enable respiratory gases to dissolve in them.
  • The lungs are also rich with a network of blood capillaries to transport respiratory gases.
 
 
The Human Respiratory Structure and Its Adaptations
  • The human respiratory structure is the alveolus which has the characteristics for efficient respiratory gaseous exchange.
  • A large number of alveoli provides a large total surface area for the diffusion of respiratory gases. 
  • The alveolus wall is always moist.
  • Oxygen and carbon dioxide can dissolve easily, and diffuse through the walls into the blood capillaries.
  • The alveolus is surrounded by a large network of blood capillaries to hasten the diffusion of respiratory gases.
  • The thin alveolus wall, that is as thick as one cell, makes the diffusion of gases much easier.
 
 
Comparison and Contrast of Respiratory Structures in Humans and Animals
Similarities
  • All respiratory structures have a large ratio of total surface area to volume for an efficient exchange of respiratory gases.
  • All respiratory structures are thin and this makes the diffusion of respiratory gases much faster.
  • All respiratory structures are moist and this allows respiratory gases to dissolve in them.
  • The respiratory structure is complete with a network of blood capillaries (except insects), that allows for efficient transport of respiratory gases.
 
Differences
Respiratory Structure How The Large Ratio of TSA/V For The Respiratory Structure is Achieved
Insect: Tracheole Large number of tracheoles
Fish: Filament and lamella Large number of filaments and lamellae
Frog: Skin and lungs The surface in the lungs is folded and the overall skin surface
Human: Alveolus Large number of alveoli

Types of Respiratory System

8.1 Types of Respiratory System
 
Introduction
  • The ratio of total surface area to volume (TSA/V) depends on the size of the organism.
  • The bigger the size of the organism, the smaller the ratio of total surface area to volume.
  • This means that for large and complex organisms, the volume of the body that requires oxygen will increase more than its total surface area.
  • This explains why large and complex organisms cannot maintain gaseous exchange by diffusion through body surface only.
  • Large organisms require a special respiratory structure for the efficient exchange of gases.
 
Adaptations of Respiratory Structures For Efficient Exchange of Gases In Big Organisms
  • Large ratio of total surface area to volume (TSA/V) for the efficient exchange of respiratory gases.
  • A thin respiratory structure that is one cell thick, allows the diffusion of respiratory gases to occur.
  • The surface of the respiratory structure is always moist for respiratory gases to dissolve in them.
  • The respiratory structure is complete with a network of blood capillaries (except for insects), that allows for the efficient delivery of respiratory gases.
 
 
 
The Insect Respiratory Structure and Its Adaptations
  • There are small pores in the thorax and abdomen of insects called spiracles.
  • The spiracle allows the intake of air into the air tube system, which is the tracheal system.
  • The trachea branches out to form finer tubes called the tracheole.
  • Tracheole is the respiratory surface.
  • The tracheole has the following characteristics that allow for efficient respiratory gaseous exchange:
    • A large number of tracheoles provides a large total surface area for the exchange of gases.
    • The tracheole wall is thin and moist.
    • This allows oxygen gas to diffuse into the cells while carbon dioxide quickly diffuses out of the cells into the tracheole.
  • Some insects have air sacs in their trachea system.
  • This sac is filled with air to speed up the delivery of respiratory gas during active body movements.
  • The breathing system of insects is the tracheal system is as follows:
 
 
The Fish Respiratory Structure and Its Adaptations
  • The respiratory structure of fish is the gills.
  • The gills are made up of a line of filament that is supported by the gill arch.
  • The following characteristics of filament enable the rapid exchange of respiratory gases.
  • The filament has many thin and flat projections called lamella (plural: lamellae).
  • A large number of filaments and lamellae gives a large total surface area for an efficient gaseous exchange process.
  • The lamella membrane is thin and supplied with many blood capillaries for easy absorption and transport of oxygen and carbon dioxide.
 
 
The Frog Respiratory Structure and Its Adaptations
Skin
  • In an inactive state, the frog uses its skin for gaseous exchange. 
  • The skin is thin and highly permeable to respiratory gases.
  • The moist skin allows respiratory gases to dissolve in it.
  • Beneath the skin, there are many networks of blood capillaries to transport respiratory gases.
Lungs
  • The surface of the lungs is folded to increase the total surface area for the exchange of gases.
  • The thin lung membrane eases the diffusion of respiratory gases.
  • The moist lung walls enable respiratory gases to dissolve in them.
  • The lungs are also rich with a network of blood capillaries to transport respiratory gases.
 
 
The Human Respiratory Structure and Its Adaptations
  • The human respiratory structure is the alveolus which has the characteristics for efficient respiratory gaseous exchange.
  • A large number of alveoli provides a large total surface area for the diffusion of respiratory gases. 
  • The alveolus wall is always moist.
  • Oxygen and carbon dioxide can dissolve easily, and diffuse through the walls into the blood capillaries.
  • The alveolus is surrounded by a large network of blood capillaries to hasten the diffusion of respiratory gases.
  • The thin alveolus wall, that is as thick as one cell, makes the diffusion of gases much easier.
 
 
Comparison and Contrast of Respiratory Structures in Humans and Animals
Similarities
  • All respiratory structures have a large ratio of total surface area to volume for an efficient exchange of respiratory gases.
  • All respiratory structures are thin and this makes the diffusion of respiratory gases much faster.
  • All respiratory structures are moist and this allows respiratory gases to dissolve in them.
  • The respiratory structure is complete with a network of blood capillaries (except insects), that allows for efficient transport of respiratory gases.
 
Differences
Respiratory Structure How The Large Ratio of TSA/V For The Respiratory Structure is Achieved
Insect: Tracheole Large number of tracheoles
Fish: Filament and lamella Large number of filaments and lamellae
Frog: Skin and lungs The surface in the lungs is folded and the overall skin surface
Human: Alveolus Large number of alveoli