HOW DO FISH BREATHE?
Discover how aquatic animals use their gills to breathe underwater
WORDS ANDY EXTANCE
G oldfish don’t look much like gorillas, but the way these creatures breathe has something in common. They both need the gas we call oxygen to survive. Oxygen helps release the energy that powers our bodies from the sugary chemical glucose in a process called respiration.
Whale sharks have five large gill slits on each side of their heads
Respiration releases another gas, carbon dioxide, which gorillas, humans and fish breathe out. Gorillas can suck oxygen you know? from the air through their mouths down into their lungs to breathe easily. Goldfish have it harder.
To breathe, fish have to pull out the molecules of oxygen dissolved in water using their gills. The amount of oxygen in the air is a lot higher than the amount of oxygen in water, though. That means that fish have a much more difficult time breathing than gorillas and humans do. Fish take water into their mouths just like we take in air, opening and closing their lips. This water then filters through the gills, organs that have lots of feathery filaments made of protein molecules.