Size Matters

size mattersUnderstanding the Surface Area-to-Volume Ratio

by Caleb Bryce, Kimberly Goetz, Pablo Barrick and Sarah Baumgart

The surface area-to-volume relationship is important for the function of both living things (ex: lung anatomy, tree roots, cell size, brain vascularization) and many human-made objects (ex: car radiators, air conditioning units). By understanding that surface area increases at a slower rate than volume as objects get larger, students can appreciate: why small cell size is advantageous; why plants benefit from a branched network of stems, leaves and roots; and why a variety of everyday objects are shaped and sized the way they are.

In this module, students learn: 1) About the relationship between surface area and volume, 2) Why this relationship is important for cells in our body.

Fellows Kim Goetz and Caleb Bryce produced this video explaining the concept of surface area to volume. A diffusion experiment using colored agar cubes, and various real life examples are used to help students understand this concept.

Docs: fulltext.docx   presentation.pptx   worksheet.docx   worksheetkey.docx
Keywords: HS-ETS1.B, HS-LS1, HS-LS1.B, HS-LS1.F, HS-LS1.G, surface area, volume