Name: _____________________ Date _______________ Dr. Sengupta
AP Biology Take Home Test on chapters 29 & 30
Due Date 2/12/09
1. Suppose you carve your initials 1m above the ground on the trunk of a mature tree
that is growing vertically at an average of 15cm per year. How high will your
initials be at the end of 2years? At the end of 20years? Explain the physiological
basis responsible for this phenomenon.
2. Porcupines often eat all of the bark off young trees, at the height they can reach.
When they do this, the tree dies. Discuss the reasoning involved.
3. Some leaves are specialized for functions other than photosynthesis. List three
other functions for which leaves may be specialized and give an example of each
4. What two cell layers are present in roots but absent in stems? What functions do
the cells of these layers perform in the roots, and why are they necessary for the
survival of the plant?
5. (a)Expert florists advise recutting the stems of flowers while holding them under
water. Explain why? (b) Some florists even advise adding ordinary table sugar to
the water in which cut flowers are placed. When this is done, certain types of
flowers will remain fresh for several weeks. What is the explanation?
6. When K+ ions move out of the guard cells, they move into adjacent epidermal cells.
How would the influx of K+ ions affect the epidermal cells? What effect would this
have on the stomata?
7. Nitrogen fixation is an energy-requiring process. What is the source of the energy
used by Rhizobium? If new symbiotic associations are developed in which the
nitrogen-fixing bacteria produce greater yields of nitrogen containing compounds,
what price is the plant likely to pay? Why?
8. Gardeners advise removing many leaves of a plant after transplanting. How does
this help the plant to survive?
9. Transpiration has often been described as a ‘necessary evil’ to the plant. Why is it
necessary? How is it evil?
10. When transplanting a plant from one place to another, it is recommended that one
include some native soil around the roots. Explain why, in terms of mycorrhizae
and root hairs.