Fish

Question 1

What is the SA to volume ratio

Answer 1

small SA to vol ratio

Question 2

Gas exchange is difficult

Answer 2

Small SA to volume ratio cannot exchange gases through skin

02= much less per unit of volume in water than air and a high viscosity and density = more difficult for fish to move

Question 3

How gills are adapted for gas exchange

Answer 3

Large SA due to lamellae
Contain counter flow between blood and water
Thin lamellae for short diffusion distance

Question 4

Counter current flow

Answer 4

Blood and o2 flow in DIFFERENT DIRECTIONS
Blood= high conc of o2 meets water= high conc of o2 means a CONCENTRATION GRADIENT is formed
This means that diffusion. Is ALWAYS happening/ possible which means the most amount of o2 is obtained