Gills would be respiration
fish breathe through their gills. frogs breathe through their legs while in water.
Circulation.
for poo.
By gills .
Respiration need transportation of respiratory gases. This is done by circulation system
Lungs and Gills are both used for external respiration
The Gills
salmon
it uses its gills
Between the lungs/gills and the environment
Like all fish- through their gills.
They have mouths and lungs. They breath oxygen from the air.