How does surface area to volume ratio relate to photosynthesis?

Question

Oliver Antoine · Accepted Answer

Surface area to volume ratio (SA:V) is important to photosynthesis because plants must balance their need for more surface area to collect sunlight with the fragile nature of the leaves and the rate of water loss.

The equation for photosynthesis is

#"6CO"_2 + "6H"_2"O" → "C"_6"H"_12"O"_6 + 6"O"_2#

A greater SA:V means more area for collection of sunlight and #"CO"_2# and less distance for #"CO"_2# to diffuse into the leaf and for #"O"_2# to diffuse out.

Thin broad leaves provide maximum SA:V, but they also means greater water loss and susceptibility to wind damage.

In drier climates the leaf surface is reduced to slender blades or even to needles to make a smaller SA:V and less evaporative surface.

For example, dill has skinny leaves and thin stems, which means increased SA:V.

Lots of surface area means that there is optimal surface to photosynthesize and produce energy for the plant.

Madeline Andrews · Answer

undefined Because it controls the efficiency of gas exchange (CO2 uptake and O2 release) and light absorption, the surface area to volume ratio influences the rate of photosynthesis. A higher ratio of surface area to volume allows for more efficient exchange of gases and light absorption, which increases photosynthetic activity.