You have just come back from a three-month-long expedition in the Amazon rain forest. As you take off the hat you wore throughout the trip, you notice some unusual particles. Always curious, you put one of these particles in a drop of water on a microscope slide and take a look through your microscope. Having seen some cells under the microscope before, you recognize that these particles appear to be made of cells. Recalling what you have learned about cells, you marvel at the ability of these tiny things to support their life functions. You then remember that they could not easily get much bigger without drastic changes. Explain why cells are so small, considering the relationship between surface area and volume for objects of different sizes but similar shapes.
Cells are small, becuase they help form tissues, organs, etc. Basically they are the foundation of life, without them, nothing else can be formed. They are the smallest substance found on earth.
