Specialised Surfaces

Question 1

What is the need for specialised exchange surfaces?

Answer 1

-single celled - high SA:V = faster simple diffusion - max absorption of nutrients - low metabolic rate

-multicellular- small SA:V = large distance - requires specialised surfaces - high metabolic rate

Question 2

What makes an efficient surface?

Answer 2

-large SA
-thin = short distance
-good blood supply/ventilation = maintenance of steep gradient

Question 3

What is the need for a specialised system for gas exchange?

Answer 3

-supply of oxygen- for production of ATP in aerobic respiration
-removal of CO2 - waste product of aerobic respiration = can alter cell pH