Fish adaptions/ special features Flashcards
What are the main adaptions of a fish
Ventilation, Gills and Counter current.
What is the function of the main adaption: ventilation
The action sequence of the mouth, buccal floor and operculum to force water over the gills so there is always fresh water.
What is the function of the main adaption: Gills
The GE surface contains lamella on the filaments. This is where oxygen enters the bloodstream and carbon dioxide leaves.
What is the function of the main adaption: Counter current
This is when water and blood flow in opposite directions in the lamellae of the gill filaments to maintain a good concentration gradient at all times increasing the diffusion efficiency.
What are the special feature of the main adaption: Ventilation
- Mouth and Mouth valves (cheek valves)
- Operculum
What is the function of the special feature: Mouth and mouth valves.
Mouth opens/ buccal floor drops, pressure decreases and water rushes in. Mouth closes, buccal floor rises (pressure increases), water is forced out open operculum, cheek valves stop the backflow of water out the mouth.
What is the function of the special feature: Operculum
Strong protective gill cover to prevent gill damage. Closes to allow water to rush in and fill the mouth. Opens to allow water under pressure to flow out over gills (unidirectional)
What are the special features of the main adaption: Gills
- Gill Rakers
- Gill arches
- Lamella
What is the function of the special feature: Gill rakers
Filter out debris so gills are not damaged or clogged
What is the function of the special feature: Lamella (on filaments)
Increases the surface area to absorb oxygen from saltwater and contains a very good blood supply to transport oxygen to cells and carbon dioxide away from cells.
What is the special feature of the main adaption: counter current
High absorption efficiency of oxygen (80%)
What is the function of the special feature: high absorption efficiency of oxygen (80%)
Due to water containing <1% oxygen the countercurrent flow of water and blood maintains a concentration gradient at all times so oxygen s efficiently moving into the bloodstream at all times.
