This worksheet can be used when studying adaptation, symbiosis, chemosynthesis or even the structure and function of animals. The tube worm is a fascinating animal that survives without a digestive tract, using the organic compounds made for them by symbiotic bacteria that live in what used to be part of their gut. My students always found this particular worm to be very interesting, as it lives deep within ocean vents where the temperature, pH and pressure is extreme. Students read the information, color the diagram and answer the questions. A good lesson for a sub or when a student has been absent. Also good for a Marine Bio, class, of course!