What is the respiratory structure?
- the respiratory surface that enables gaseous exchange to occur between respiring organism cells and their outer evironment
How are the respiratory structures of large-sized organisms adapted for
efficient exchange of gases? (5)
- 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.
Explain the insect respiratory structure. (4)
- breathing system is the tracheal system
- spiracles in thorax & abdomen allows intake of air into the air tube system (tracheal system)
- trachea branches out to form tracheole (respiratory surface)
- some insects have air sacs (speed up delivery of respiratory gas during active body movements)
What are the adaptations/characteristics of the tracheole that allows efficient respiratory gaseous exchange? (2)
– 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.
What are the fish respiratory structure and its adaptations?(4)
-respiratory structure is gills
- gills made up of filament supported by gill arch
Adaptation of lamella for rapid exchange of respiratory gases:
- filament has many thin & flat projections called lamella (large number of filament & lamellae gives large TSA for efficient gaseous exchange)
- lamella membrane is thin & many blood capillaries for easy absorption & transport of oxygen & carbon dioxide
What is the frog respiratory structure & its adaptations?(skin:3, lungs:4)
When inactive, frog uses 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 (Figure 8.3).
• 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.
What is the human respiratory structure and its adaptations? (5)
- respiratory structure is alveolus
characteristics of alveolus 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.
Similarities between the respiratory structures of humans and animals (4)
- 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 between the respiratory structures of humans and animals (2 characteristics)
Respiratory structure:
Insects:
-Tracheole
Fish:
-Filament and lamella
Frogs:
-Skin and lungs
Humans:
-Alveolus
How the large ratio of total surface area to volume for the respiratory structure is achieved:
Insects:
Large number of tracheoles
Fish:
Large number of filaments and lamellae
Frogs:
• The surface in the lungs is folded
• Overall skin surface
Humans:
Large number of alveoli
