UNIT ONE • LESSON EIGHT Pert. 2 Group Discussion • Did you get similar results for the celery and Whet. IP? carnations? • Were there different results for different lengths Ask students: If you could change one thing about Maving Cln Up: of carnations or celery? this investigation to learn something new, what •Where do you think the water goes once it gets would you try? When we change one part of an r===Capillary J\cliian I to the top of the plant? experiment to see how it affects our results, this • What did you learn about water from this ex­ change is known as a variable. Use the chart in periment? be drawn through the your journal to record your ideas about what might Have you ever wondered • Did everyone have the same results? how water gets from narrow capillary tubes happen if you change some of the variables. Some •What did you like about this investigation? 1.eerning the roots of a tree to inside the plant. For possibilities are: • What variables did you try? capillary action to occur, • Will you get the same results if you use different Clbjecliive& its leaves, or why pa per •What surprised you? towels are able to soak up the attraction between the quantities of water or different amounts of food a soggy spill? It has to do water molecules and the coloring? Students will: The "Why" and The "How" tree molecules (adhesion) • What if you use soapy water? Salty water? Cold with the property of water This investigation illustrates the property of water known as capillary adion. must be stronger than the water? Hot water? 1. Explain why known as capillary action. Capillary action is water t ravels mutual attraction between • Will it make a difference if you use slightly wilted how trees and plants get water to travel upwards through certain all water molecules carnations or celery? Capillary action is from their roots to their leaves and flowers. materials by water's ability to move (cohesion). • What if you tried a different type of plant? All trees and plants have tube-like capillaries capillary action. through the narrow • If you use another liquid, will you get the same called "xylem" (zi-lem). Water molecules like to tube-like spaces, known Water's surface tension, results? 2. Investigate stick together and to the inside walls of plant as capillaries, within a the property of water how water can capillaries, so they rise up in the tubes until they porous or spongy material. which causes an invisible We encourage you to try these variables or other travel through reach the top of the plant. Water eventually Capillary action even "skin" to form on the ideas suggested by the students. Invite students to the capillaries mangrove tree with evaporates (changes from a liquid to a gas) from allows water to climb surface of water, also share their questions and results with the group and of different exposed roots the leaves and petals of the plant by a process upwards against the force has an important role in record their findings in the chart in their student materials. known as transpiration. capillary action. Inside a journals. of gravity. This is how 3. Test variables water is able to travel from capillary, the surface of Capillary action is limited by In this investigation, the colored water climbed during the the roots to the leaves of a water forms a concave gravity and the size of the up through the narrow capillaries of the celery capillary action tall tree. shape (like the letter C) capillaries or tubes. Water W"IU\P-UP and carnations. As the colored water moved experiments. called a meniscus. This will stop moving upwards upwards it outlined the path of the capillaries Plants absorb water from is because the force ad through a capillary once it To wrap-up the investigation, bring your students in each plant's stem/stalk, leaves and petals, the soil through their adhesion causes surface is unable to overcome the together for a group discussion to help them un­ resulting in a change of color. roots. When water enters water molecules near the force of gravity. The size of derstand why and how they achieved their results. the soil and reaches the capillary walls to move a capillary also determines It is important to share results so that everyone roots of the tree, water through the capillary first. how high the water can go. has a clear picture of what happened. To help you molecules are attracted to As these molecules move, The thinner the capillary facilitate the discussion, review the explanation in the molecules in the root. surface tension keeps tube, the higher up capillary "The Why and The How" using the Group Discussion This process is known as the surface of the water action will pull the water. questions as a guide. CurriculuM Melich-Up adhesion, and it happens together and causes it to Capillary action can draw Vacebulery when water molecules are form a bowl shape. The water up into a tree over Group Discussion • Graph the distances the water t raveled in Venliure& attracted to molecules in water molecules beneath 300 feet tall! Explain to students that scientists learn from each the celery and carnations for a particular other substances. This the surface tag along due other through discussion, and they build upon the time period. adhesion attraction causes the water to cohesion. • Create a graph for the time it took for the work of others to make new discoveries. Just as sci­ capillary molecules to move closer entists come to conclusions based on the findings of water to travel all the way up the celery to the root molecules and their experiments, they will now come together as and carnations. capillary action a group to share their results and make conclusions • Graph the speeds or distances for different about the investigations they've conducted. Have colored water. cohesion students record their final results and the explana­ • ReReat the experiment using other mate­ gravity tion in their journals. ri a f~ uch as cotton string. What do you observe? meniscus 1lMe w.lecl ta CDndll:t. lnvelt.Jpt,lan surface tension This investigation has two parts. Organize and set up materials: 10 minutes Introduce the lesson: 1O minutes References: Conduct the investigation: 20 - 30 minutes www.ed.gov/pubslparents/Science/celery.html This lesson was funded in (whole or part) with federal funds from Title Student journaling/group reflection: 10 minutes www.stevespanglerscience.com/experi ment/00000144 IV, Part B, 21st Century Community Leaming Centers program of the No Total estimated t ime: 50- 60 minutes Toothpick star in Water, water everywhere and not a drop to spare! New Child Left Behind Act of 2001 awarded to the New Jersey Department of Jersey Academy for Aquatic Sciences. Education. 21st CENTURY AFTERSCHOOLSCIENCE PROJECT (21st CASP) UNIT ONE • LESSON EIGHT PAGE 4 21st CENTURY AFTERSCHOOLSCIENCE PROJECT (21st CASP) UNIT ONE • LESSON EIGHT PAGE 1 celery vessels with food coloring

split carnation set-up