Stacks of two thin plates on each gill that increase surface area
Lamellae
A single layer of flattened cells on the gill filaments
. Increase surface area
. Short diffusion pathway
Opperculum
Muscle that protects the gills, opens when water is pushed out of the gills
Picture
.
Picture
.
Counter current
. Water flows past the lamellae in the opposite direction to the blood flow, this is called counter current and maintains a constant concentration gradient for O2 to keep diffusing through into the blood and CO2 out
