Leaves are the "food factories" of plants. Unfortunately, studying photosynthesis directly requires fancy equipment that is not easily available to school teachers. However, making sugars through photosynthesis is not the only way leaves interact with the environment. In this study you will have a chance to investigate first hand the process of transpiration, or the loss of water from plants via evaporation.
What do you wonder about transpiration? Brainstorm for a minute with your teammates and then decide on a question you'd like to answer. You'll have enough materials to compare water loss from the leaves on several twigs between now and next week. You might want to compare leaves in different micro-environments, (e.g., sunny vs. shaded) of two kinds of plant (e.g., oak vs. maple). You also will have to consider how many replicates you will need so that you will have confidence in your results.
Decide on what comparison you want to make, then select and bag branches.
2. Collecting data about transpiration.
Teacher's Study PlanQuestion1. Write the question you will answer with your study.
Hypotheses2. Write the "null" hypothesis you are testing.3. Write an alternative hypothesis you are testing.
Methods4. Describe how you will address your question. Give specific details about your methods.5. Draw a map showing the location of your sampling sites and/or a diagram showing what your sampling scheme looks like.
Anticipated Results6. What do you expect to find? You might want to draw a graph of your predictions on the back of this sheet.
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