How big are cells? - Unit 3 Lesson 1 (continued)
It is very helpful to get a sense of the scale of what we are talking about when we learn about cells. Just how big are they? Well, pretty small. You need a microscope to see them. But, there are also things smaller than cells. In lesson 2 we will look at the structures that make up the insides of cells. And, of course, there are things that make up those structures! And there are things that make up those things. We could on and on.
But I digress. We were talking about the size of cells. Page 193 in your textbook has a diagram showing the size of cells. But it doesn’t compare the size of cells compared to, say, a grain of sand. It’s helpful to really understand the size of what we are talking about. That’s where this simple web app from the University of Utah can help us. Use the scale to zoom in. Notice how you can just barely make out the skin cell when the grain of salt is still in the frame.