Q1. What chemical do secondary cells walls contain that is not found in primary walls and how does it affect strength and digestibility of the secondary walls?

Q2. Terry suffers from dissociation of memories from their emotional content as the result of an automobile accident. What system of the brain is most likely damaged?

Q3. What must a biologist do if she or he finds that different methods of analyzing the same data give different estimates of the relationships among certain taxa?