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Exercise 1A: Scaling Applied to Leaves
Equipment:
leaves of three sizes, having roughly similar proportions of length, width, and thickness
(example: blades of grass, large ficus leaves, and agave leaves)
balance
1. Each group will have one leaf, and should measure its surface area and volume, and determine its
surface-to-volume ratio (surface area divided by volume). For consistency, every group should use
units of cm
2
and cm
3
, and should only find the area of one side of the leaf. The area can be found by
tracing the area of the leaf on graph paper and counting squares. The volume can be found by weigh-
ing the leaf and assuming that its density is 1 g/cm
3
, which is nearly true since leaves are mostly water.
Write your results on the board for comparison with the other groups’ numbers.
2. Both the surface area and the volume are bigger for bigger leaves, but what about the surface to
volume ratios. What implications would this have for the plants’ abilities to survive in different environ-
ments.