Questions for Further Thought
These questions encourage you to think in more detail about topics covered in this lab. Becaure they are thought questions, there aren't necessarily single "right" answers. Don't be surprised if some of these questions reappear on a quiz or midterm.
- What distinguishes a root from a rhizome? From an evolutionary perspective, why might this distinction be important?
- How would you define a "tree"? Tuck your definition away for a few weeks until we study the arborescent lycopsids of the Paleozoic-are they "trees" or overgrown "herbs"?
- "Cavitation" is the process of bubbles forming in xylem. When such bubbles form (say by an ice crystal shrinking as it thaws to liquid), they break the continuous chain of water molecules from root to leaf and render the xylem non-functional. What sort of ecological implications might this phenomenon have for the plant?
- Are the conducting tubes in tracheophytes and bryophytes homologous? What additional information would be needed to increase confidence in your answer?