Lesson Title: “The Plant Factory”
By Kate M. Faris
Description
In this activity students will learn about the stems of plants and capillary
action; students will also compare how quickly plants “drink” or absorb when missing an organ.
Grade level(s) 3rd Grade
Essential questions
· What affect would there be on a plant if one of its major organs were missing?
· Do leaves make a difference in the speed of capillary action?
Student learner objective – connections to the GLE’s
· Identify the major organs (roots, stems, flowers, leaves) and their functions in vascular plants (e.g., absorption, transport, reproduction). (DO NOT assess the term vascular) (LO.1.D.a) (1.6; 1.8; 3.5) DOK - 1
· Illustrate and trace the path of water and nutrients as they move through the transport system of a plant. (LO.2.C.a) (1.2; 1.3; 1.4) DOK – 1
· Describe the basic needs of most plants (i.e., air, water, light, nutrients, temperature). (LO.1.A.a) (1.2; 1.3; 1.6; 3.1) DOK – 1
· Read and interpret information from line plots and graphs (bar, line, pictorial) (D1C3) (1.10) DOK 2
Featured Scott Foresman’s textbook
· Scott Foresman, 2006,TE pp. 4-29, 106, 150-151, 359-461
· Scott Foresman Leveled Readers, TE Chapter 1: Plants and How They Grow, Plants and Trees Growing, Tree Life
Featured picture books
· From Plant to Seed, by Gail Gibbons
· The Tiny Seed, by Eric Carle
Time needed
About 90 minutes
Academic vocabulary words (with definitions)
roots- The roots of a plant soak up vitamins and minerals. They also store food for the
plant- A young tree, vine, shrub, or herbplantedor suitable forplanting
stem- The stem supports the plant. It has many thin tubes that carry water, minerals, and food through the plant
flower- A flower is the part of a plant that makes seeds.
leaves- The leaves make food (sugar) for the plant. They also take in carbon dioxide and release oxygen into the air
absorption- Process in which the plant sucks up water from the ground
transport system- a facility consisting of the means and equipment necessary for the movement of passengers or goods
growth- The process of growing
life cycle- a series of stages through which an organism passes between recurrences of a primary stage
Depth of knowledge level
DOK 3
Materials needed
· Fresh bunch of celery with leafy tops
· A few containers filled with about 6 inches of water
· Red or orange food coloring
· Timers
· Knife and cutting surface
· Rule
Lesson narrative:
Engage
Read one of the picture books to the class and talk about the basic needs of plants. Focus the conversation on water and begin to question how plants “drink”. Ask the students how they think plants drink and what parts of the plant help it drink, do you think the leaves help the plant drink? Have the students discuss this in a small group and come up with why the leaves help or not. Ask them how we could test this question to find out.
Have prepared for the students some celery that has already absorbed some of the red food coloring. Ask them how they think I made the celery have the red in it, record observations on the board. Some may have seen this activity already, but that’s ok because we are going to see if they think the leaves will make a difference or not.
Explore
1. Tell students they are going to conduct an experiment to learn more about capillary action.
2. Cut off the bottom inch of the celery bunch while it is submerged in the tub of water. Stand the bunch upright and then remove all the leaves from half of the stalks and place them in a separate container. Finally, add food coloring to the water.
3. Have students hypothesize how capillary action might be different between stalks with leaves and stalks without. List their hypotheses on the board or a flipchart, indicating how many students chose each one. Have students create a bar graph showing this information.
4. Place the celery tubs in a sunny location and remove two stalks every 20 minutes – one with leaves and one without. Cut each stalk in five centimeter sections, from the bottom edge up, until no color can be seen in the celery. Continue until no stalks remain or until the colored water has been siphoned to the top of at least one stalk.
5. Have students evaluate their hypothesis and decide which one was supported by the results in the experiment.
Explain
Do leaves make a difference in the speed of capillary action? Celery stalks with leaves have a greater amount of transpiration. Water leaving the plant through the leaves helps pull more water into the plant and up the stems
There are two things that combine to move water through plants --transpirationand cohesion. Water evaporating from the leaves, buds, and petals (transpiration) pulls water up the stem of the plant. This works in the same way as sucking on a straw. Water that evaporates from the leaves "pulls" other water behind it up to fill the space left by the evaporating water, but instead of your mouth providing the suction (as with a straw) the movement is due to evaporating water. This can happen because water sticks to itself (called water cohesion) and because the tubes in the plant stem are very small (in a part of the plant called thexylem). This process is calledcapillary action.
Elaborate/Extend
I would want to ask students if they feel as if this just applies to celery or if it would be the same for all plants with leaves. I would also want them to come up with testing a flower with and without the leaves and also with and without the flower.
(Project BudBurst also offers a lesson on how plants breath through their leaves; this would be a great follow-up activity after this lesson)
Magic School Bus- Gets Planted, also does a very nice job of visualizing the process of the roots “drinking” the water and then the water traveling up the stem.
Use the Kestrel to see how the temperature effects the rate of absorption in different types of plants.
Evaluate
Have students fill out the graphing template and create a “flash statement” a statement they can make about the graph just by looking quickly at the graph. For my higher students I might give them a plain piece of graphing paper for them to label and for my SPED students I would fill in some of the information on their graphing template.
Misconceptions
I feel as if the students will think that with the leaves missing the water will move faster, but in all reality, the leaves help the capillaries absorb water at a faster rate.
Safety
The teacher should be in charge of the knife of all times so accidents don’t happen.
Reading comprehensive strategies
· Inferencing: Students can use their prior knowledge and information from the book to come up with ideas about plants.
· Predicting: Students will use information from the picture books and their text book to make a prediction about how plants “drink”.
· Looking for important information: students will decide what they feel is important when reading the text and talk about what is important while they are conducting their experiment.
General suggestions for students and teachers
I will be doing this lesson in about four small groups so the students can then compare their results with other groups. I will be in charge of the knife so groups will need to start the activity about five minutes apart so I can visit with each group and have them measure where to cut.
Create a “parking lot” in the classroom so while students are exploring and coming up with other questions and other ideas to test, you can write them on a post it so you can research them later.
Bibliography
· http://neoninc.org/budburst/educators/pdf/PBB_waterchain.pdf
· http://www.stevespanglerscience.com
· www.superteacherworksheets.com
· www.education.com
Student Pages
(see below)
Name:______Date:______
Draw a picture of both plants before they Draw a picture of your plants after they were in the colored
were put in the colored water. water.
Describe how the celery stalk changed:______
______
______
How does water travel through the celery?______
______
Did the leaves on the celery make a difference at all?______
______
Minutes in Water / Observations0 minutes
20 minutes
40 minutes
60 minutes
Celery with Leaves
Celery without Leaves
Minutes in Water / Observations0 minutes
20 minutes
40 minutes
60 minutes
Minutes in Water / Observations
How far has the colored water traveled?
(in centimeters)
0 minutes
20 minutes
40 minutes
60 minutes
Minutes in Water / Observations
How far has the colored water traveled?
(in centimeters)
0 minutes
20 minutes
40 minutes
60 minutes
Which plant absorbed the water faster?______
Why do you think this is?______
______
______
Compare your results with two other groups. Did your results seem to be the same of different? If they were different, what would have made them different?
______
______
Comparing Plants, with and without Leaves, Absorption Rate of Water