Some organisms take in oxygen using a respiratory system.
In humans, gas exchange takes place in the lungs.
Name the organs where gas exchange takes place in fish.
How to approach this question
Recall the structure of a fish. What specialised organs do fish have to extract oxygen from water?
Full Answer
Gills
Different organisms have different adaptations for gas exchange depending on their environment.
- **Humans** and other terrestrial mammals live in air and use internal **lungs** for gas exchange.
- **Fish** live in water and have developed specialised organs called **gills** to extract dissolved oxygen from the water. Gills consist of many fine filaments that create a large surface area for efficient diffusion of oxygen from the water into the fish's blood.
Common mistakes
✗ Naming the human organ (lungs).\n✗ Giving a general term like "respiratory system".
Expert