1. Explain why transpiration rate tends to be greatest under conditions of low humidity, bright sunlight, and moderate winds.
2. Describe the anatomy of xylem tissue and explain why it is an efficient system for the transport of water through the plant.
3. Trace the path of water from the soil, through the root, stem, and leaf of a plant, and into the atmosphere.
4. Explain how water can be moved to the top of a 100 m tree, but a mechanical pump can lift water no higher than about 10.3 m. What prevents the water column in a tree from breaking? Under what conditions might the water column break, and, if it does break, how is it reestablished?
5. Many farmers have found that fertilizing their fields during excessively dry periods can be counterproductive, as it may significantly damage their crops. Based on your knowledge of the water economy of plants and soil, explain how this could happen.
6. Does transpiration serve any useful function in the plant?
7. Explain the relationships between field capacity, permanent wilting percentage , and available water. Even though permanent wilting percentage is based on soil weight , it is often said to be a property of the plants. Explain why this might be so.