We’re guessing you’re fond of protein shakes because they help repair and regrow damaged muscles. Score one for you. But aside from knowing that, do you think your knowledge about protein could fit into a shaker bottle?

If not, this Protein 101 refresher will help bring you up to speed. For a crash course, we turned to nutrition and fitness expert Lisa Lynn, frequent guest on NBC’s The Dr. Oz Show and author of The Metabolism Solution.