Book excerpt: There's no need for expensive, high-tech lab equipment to perform biology experiments—you probably have all you need in your home junk drawer. Use balloons, drinking straws, and empty plastic bottles to construct working models of hearts and lungs. Investigate plant transpiration and photosynthesis with leaves and resealable bags. Build a candy DNA model using gumdrops, toothpicks, and licorice rope. Study capillary action in plant xylem using colored water and paper towels. Extract DNA from a banana using a simple chemical process. Or learn how to turn a smartphone into a photographic microscope. Here are more than 50 great hands-on experiments that can be performed for just pennies . . . or less. Each project has a materials list, detailed step-by-step instructions with illustrations, and a brief explanation of the scientific principle being demonstrated—seed germination, osmosis, human senses and systems, chromosomes, mitosis and meiosis, and more.