Gill Introduction

The gills of fishes have the same basic exchange function of the lungs of birds and mammals. They must provide a large surface area for gas diffusion across a narrow water/blood barrier. Gill anatomy varies among different types of fish; we will examine those in typical telosts, the Bass and Medaka. Providing exchange between blood and water creates some difficulties for fish due to smaller O2 gradients and osmotic water movments. Note how in many ways the organization of the fish respiratory system resembles that of birds and mammals but is different so as to function in an aquatic environment.