surface area to volume ratio

Question 1

what is the relationship between the size of an organism and it SA:V

Answer 1

smaller organisms have higher SA:V
can be proven mathematically

Question 2

what is the relationship between SA:V and metabolic rate

Answer 2

rate of heat loss increases as SA:V increases
so they need a higher metabolic rate
to generate enough heat to maintain a constant body temperature

Question 3

what are the adaptations to facilitate exchange as the SA:V reduced in larger organisms

Answer 3

need a specialised surface for gaseous exchange eg. lungs
smaller SA:V and a long diffusion pattern h
and have a high demand for oxygen and to remove carbon dioxide