Do cells have size limits? Cells can range from 2m to 200m (10m). m = millionth of a meter or m Most eukaryotic cells are about 10m. Not visible with the naked eye. Let's put this into perspective!! This means that an infants cells are the same size as an adult or teenager. Eukaryote cells all have similar sizes. They increase cell numbers to grow. Why do Eukaryotes have so many cells? Why do we not have just 1 cell or 10 cells? There is still lots of cell variety!!! Muscle Cells Epithelial Cells (skin) Nerve Cells These cells may look very different, but are all about the same size. Shapes may change, but sizes are constrained!! Why?? Red and White Blood Cells Plant cells Microvilli in the small intestine Branches in Lungs Anemones many tentacles Trees and their broad/flat leaves Increasing Surface Area for individual cells is also important. Consider : What are all these adaptations trying to accomplish for the organism? What measurements represent the cell membrane? The cytoplasm? Does the distance from the center increase or decrease from model to model? Which cell is best able to interact with its environment? How can cells increase their total surface area to volume ratio?