TED Talks
Ted: Ted Ed: How Mucus Keeps Us Healthy
Your body produces more than a liter of mucus every day, and when you're sick, it can be hard to miss. But what exactly is mucus? And what does it do, besides making you miserable? The following video and learning guide reveals the...
University of Hamburg
University of Hamburg: The Cell Wall
This site provides a description of primary and secondary cell wall. Includes an image of cell wall structure.