Virtual Lab: Plant Transpiration
Objective: To understand plant transpiration and how it affects a plant’s survival.
Click above to “Enter Virtual Lab.” On the top right of the computer screen, click on “Information” and complete the beginning of this lab.
Information Fill-in Word Bank (5 points)amount leaves release transpirationcapillary action narrow roots upward environment open stem vascularevaporation photosynthesis stomata waterintake rate time
In _________________ plants, water is absorbed through the roots and carried
_________________ through the _________________ to the ________________. The force
behind this upward movement is called _________________ _________________ , a force of
attraction between molecules that causes liquids to move up _________________ tubes, such
as those inside a plant's stem.
Some of the water absorbed by a plant's roots is used for _________________ , but much is
lost to the _________________ through a process called _________________ . During
photosynthesis, tiny pores on the surface of the leaves, called _________________ , open to
permit the _________________ of carbon dioxide and the _________________ of oxygen.
Because the stomata must remain _________________ for the exchange of gases, large
amounts of _________________ are lost to the environment through _________________ .
Water that evaporates from the leaves is continually replaced with water that is absorbed
through the _________________ . Therefore, a plant's _________________ of transpiration
can be measured by observing the _________________ of water taken up through a plant's
roots over a period of _________________ . The transpiration rate can be approximated by
measuring the amount of water taken up in a short time through the plant's stem.
Name: ______________________________________________ Class: _________________ Date: ________________
Enter Virtual Lab Here
Read the description of the laboratory setup in the Question section of the virtual lab (on the left of the computer screen).
PRE-LAB (5 points)
Match the environmental factor to the correct equipment used in the lab to simulate these factors.
Factor Equipment usedSunlight Temperature Wind
HYPOTHESIS (4 points)I think that, on average, plants exposed to the ______________________ will have (environmental condition) the _____________________ transpiration rate. (highest/lowest)
Laboratory Setup and Procedure (6 points)In a laboratory, a plant's transpiration rate can be measured using a potometer.
Draw a sketch of the lab setup and label the following: 1) plant sprig, 2) burette and pipette, 3) water, 4) environmental factor (lamp, heater, fan), 5) clock, 6) thermometer
Laboratory Procedure Sketch
DATA: Collect, calculate the average, and GRAPH the data. (10 points)Amount of Water Transpired in 1 Hour (mL)
Plant Type Normal With Fan With Heater Lamp
Average Rate of Transpiration
(mL/hr)
ANALYSIS (35 points)
1. Describe the process of transpiration in vascular plants.
2. Circle all of the experimental controls used in the Investigation. Place a rectangle around the independent variable and underline the dependent variable.
Type of plant fan, lamp, or heater
Time Photometer
Amount of water transpired Type of test tube used
Temperature of the lab
3. What environmental factors that you tested increased the rate of transpiration? Was the rate of transpiration increased for all plants tested?
4. Did any of the environmental factors (heat, light, or wind) increase the transpiration rate more than the others? Why?
5. Which species of plants that you tested had the highest transpiration rates? Why do you think different species of plants transpire at different rates?
6. Suppose you coated the leaves of a plant with petroleum jelly. How would the plant's rate of transpiration be affected?
7. Of what value to a plant is the ability to lose water through transpiration?
CONCLUSION (15 points)
Write a 3-5 sentence summary of what you learned in this lab:
GRAPH (20 pts)
5 pts Title
5 pts Both X & Y axis are labeled
5 pts Accurate increments used on both axis’
5 pts Color used on graph & legend (key)