Gas exchange Flashcards
1
Q
Structure of fish gills
A
They have lamellae which are hair like structures and they increase the surface area
2
Q
Countercurrent exchange
A
blood and water flow over the lamellae in opposite directions. Blood that is loaded with oxygen meets the water with maximum concentration of oxygen so diffusion can take place. Blood with little oxygen meets with water that has most of its oxygen removed, diffusion can take place
3
Q
Gas exchange in plants
A
Thin, flat shape that provides a large surface are
Many small pores called stomata
Interconnecting air spaces, for a shorter diffusion pathway
4
Q
what affects the rate of diffusion
A
Concentration gradient is increased
surface area is increased
thickness of exchange surface decreased
