Fish extract oxygen from water using their gills, not by converting water into oxygen.
How Fish Gills Work
Fish use their gills to extract dissolved oxygen from water. Here's a breakdown of the process:
Gill Structure
- Gill Filaments: Gills are made up of numerous filaments.
- Lamellae: Each filament has thousands of tiny folds called lamellae. These folds significantly increase the surface area exposed to water.
Oxygen Extraction Process
- Water Flow: Water flows over the gills, coming into contact with the lamellae.
- Oxygen Diffusion: Dissolved oxygen in the water passes through the thin membranes of the lamellae.
- Entry into Bloodstream: The oxygen then enters the fish's bloodstream.
- Carbon Dioxide Elimination: At the same time, carbon dioxide from the fish's blood is released into the water and eliminated.
Summary Table
| Step | Description |
|---|---|
| Water Flow | Water passes over the gill filaments and lamellae. |
| Oxygen Diffusion | Oxygen from the water diffuses through the thin membranes of the lamellae. |
| Bloodstream Entry | Oxygen enters the fish's bloodstream. |
| Carbon Dioxide Release | Carbon dioxide from the blood is released into the water and eliminated. |
Key Points
- Surface Area: The extensive surface area of the lamellae is crucial for efficient gas exchange.
- Thin Membranes: The thin membranes of the lamellae allow for easy diffusion of oxygen and carbon dioxide.
- Continuous Process: This process is continuous, ensuring a steady supply of oxygen to the fish and removal of carbon dioxide.
