exchange surfaces

Question 1

how do you find the area of a surface

Answer 1

length X width

Question 2

do multicellular organisms have a small surface area

Answer 2

have a smaller surface area compared to their volume - not enough substances can diffuse from their outside surface to supply their entire volume

Question 3

exchange surfaces are adapted to maximise effectiveness

Answer 3

. they have a thin membrane, so substances only have a short distance to diffuse
. they have a large surface area so lots of a substance can diffuse at once
exchange surfaces in animal have lots of blood vessels, to get into and out of the blood quickly
. gas exchange surface in animals are often ventilated too - air moves in and out