1. List the systems that had to evolve to support cellular respiration in multi-cellular animals? (I can come up with three, how about you?). 1. 2. 3. 2. List the systems that either evolved by piggybacking on the ones above or evolved to compensate for potential problems caused by the systems listed above. (I can come up with three, how about you?). 1. 2. 3. 3. Structure/Function: List all the adaptations that increase surface area in animal systems and explain why increased surface area improves the function of that system. (I can come up with at least seven, how about you?). 1. 2. 3. 4. 5.