Respiration
gas exchange
The capillaries are responsible for gas and nutrient exchange with each of the body's cells.
Gas exchange between the body and the environment occurs in the lungs.
lunges
the alveoli in the lungs and the capillaries in the body
respiratory
suffocation
Diffusion
Breathing.
The alveoli
It's because a process called gas exchange has taken place in the fish's body. Oxygenated blood is pumped throughout the body, and the cells in the body take out oxygen and put in carbon dioxide (gas exchange). The blood returning to the heart of the fish is deoxygenated, and it will have to eventually go to the gills. There, the carbon dioxide (CO2) will get dumped into the water and oxygen (O2) will be picked up from the water at the same time in another gas exchange.
cutaneous gas exchange