Gaseous exchange is the movement of Carbon dioxide and
oxygen across the respiratory surface.
In unicellular organisms carry out gaseous exchange by
diffusion across the cell membrane while large organism cannot carry out
diffusion efficiently so they developed specialized organs for gaseous exchange,
these are called Respiratory surface.
Respiratory surface is the specialized organ or place
where gaseous exchange takes place of an individual.
Example of respiratory surface in various organisms.
Example of respiratory surface in various organisms.
Organism
|
Respiratory
surface
|
|
1
|
Amoeba
|
Cell
membrane
|
2.
|
Insect
|
Tracheal
system
|
3
|
Spider
|
Book
lung
|
4
|
Fish
|
Gills
|
5
|
Plants
|
Leaves,
Roots, stems
|
6.
|
Amphibians
|
Skin,
Gills, Lungs
|
7
|
Mammals
|
Lungs
|
8
|
Reptilian
|
Lungs
|
9
|
Birds
|
Lungs
|
Characteristics of respiratory surface
1. They are thin so that the gases diffuse over a short
distance
2. They are moist to dissolve the gases so that they
diffuse in solution form
3. They are branched, highly folded or flattened in
order to increase the surface area for gaseous exchange
4. They are closer to an efficient transport system so
that gases can be taken to and from the cell easily
5. They are well ventilated so that gas can pass
through them easily.