Gas Exchange - Bony Fish Flashcards Preview

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Flashcards in Gas Exchange - Bony Fish Deck (7)
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What is the structure of the gas exchange system in bony fish?

Operculum protects gills.

Gills on each side of head

Gillarch has two stacks of filaments with lamellae.

Capillaries surround the lamallae.


How do fish maintain a current of water?

Takes in water through the mouth and forces it through its gill slit which maintains a concentration gradient and water flows out through the operculum.


What are the lamellae?

The surface is a single layer of flattened cells next to a network of capillaries, which are close to the surface so oxygen has a short diffusion distance.


How does water move into the mouth?

Mouth opens
Operculum closes
Floor of mouth lowered
Volume inside buccal cavity increases, pressure decreases
Water flows into buccal cavity.


How does water move out of the mouth?

Mouth closes
Floor of mouth raised
Volume of buccal cavity descreases, pressure increases
Operculum opens
Water flows over gills into opercular cavity and out


What is the parallel flow system (in sharks- NOT BONY FISH)?

The water flows in the same direction of the blood.


How does water flow in a bony fish?

Diffusion can occur across the entire gill lamella because O2 concentration in H2O is always higher than in the blood.