The Weight of a Cell
Ella Watkins-Dulaney Microbes are so small that tens of thousands could fit in the space of the period at the end of this sentence. And yet, for two of the most widely studied kinds — S. cerevisiae and E. coli — we know their weight with remarkable precision: A single yeast cell weighs about 100 picograms and a single E. coli bacterium weighs about one picogram, or 60 million times less than a grain of sand. At first blush, measuring the weight of a single cell seems an impossible task. How ca