Q1. Three classes, the Polychaeta, Oligochaeta and Hirudinea, will be examined. Class Polychaeta Members are marine. Polychaetes have lateral, fleshy parapodia beset with numerous setae, and well developed head appendages such as jaws, tentacles and eyes. What function(s) do you think about parapodia serve?

Q2. A mammal uses only 1 to 2 percent of its energy in ventilation (breathing air in and out) while a fish must spend about 15 percent of its energy to move water over its gills. Clarify this huge difference in their efforts to collect oxygen.