Fish Ventilation

Question 1

How is the surface of the lamellae structured?

Answer 1

The lamellae surface consists of a single layer of flattened cells that cover a vast network of capillaries

Question 2

What is the counter current system?

Answer 2

lamellae ensures that the blood flow is in the opposite direction to the flow of water.

The counter-current system ensures the concentration gradient is maintained along the whole length of the capillary

The water with the lowest oxygen concentration is found adjacent to the most deoxygenated blood

Question 3

why do fish require specialised gas exchange systems>

Answer 3

• small SA:V
• scaly exterior
• large diffusion distance; diffusion alone would not be enough to supply their inner cells with the oxygen required.