Ready for Roots

Lesson Introduction

Inside each seed is an embryo which consist of the basic parts from which the seedling develop including its supply of food. The food is needed to keep the seed alive and few its process of germination or growth. For weeks, months, or even years the seeds may be inactive. But when conditions are right, the seed begins to grow. During germination the seed absorbs water, the cells of the embryo start to divide and the seed case breaks open. First the root system sprouts and grows down, followed by the shoot which will produce the stem and leaves.

Illinois State Goal	Standard	Learning Benchmarks
10	A	2a. Organize and display data using pictures, tallies, tables, charts, bar graphs, line graphs, line plots and stem -and- leaf graphs.
10	B	2b. Collect, organize and display data using tables, charts, bar graphs, line graphs, circle graphs, line plots and stem-and-leaf graphs.
11	A	2b. Collect data for investigations using scientific process skills including observing, estimating and measuring.
11	A	2c. Construct charts and visualizations to display data.
11	A	2e. Report and display the results of individual and group investigations.
12	B	2b. Identify physical features of plants that help them live in different environments.

Lesson Objectives

The students will:

• classify different seed type by appearance
• germinate several different types of seeds
• graph seed growth diagram seed growth

Advance Preparation

Time Allotment

45-50 minute session

Materials

(per group 4-6 students)

• 1/4 in. layer of cotton or 3 paper towels
• masking tape
• 1 small envelope containing 5-6 of each seed (popcorn, bird seed, grass seed, beans)
• 1 hand lens
• small plastic tray or shoebox-like container

PROCEDURE

Tap Prior Knowledge

1. Ask the students if they know where adult plants come from. Does anyone have a guess as to how the baby seed becomes a full grown plant? Do all plants grow the same way? Accept all answers.

Share with Neighbor

2. Give each group their seeds. Ask the students if they can spot any differences between the seeds. Ask them to sort or classify their seeds into groups that seem similar to one another. Can anyone guess what kinds of seeds they have?

Hands-on Activity

3. Have one student dampen the paper towels. Make sure that the paper towel or cotton is not too wet or the seeds will mold.

4. Have another student place one of the damp paper towels, or cotton layers on top of your plastic tray (or along the bottom of your plastic container).

5. Instruct two of the group members to lay each group of seeds on top of the paper towel or cotton. You may wish to have the students label the different kinds of seeds and where they are.

6. Cover the seeds with another damp paper towel or cotton layer.

7. Have each student make a drawing that predicts what their seed will look like after one week.

8. Observe the seeds several times over one week. Have the students draw what their seed actually looks like in comparison to their predictions.

Introduce Scientific Principle/Environmental Issue

9. Once the seeds begin to germinate, the students should make daily observations. They can draw what they see in addition to measuring their seed's growth.

10. Each one of their seeds contained all that it needed to grow, but it would not begin to grow until all conditions were right. The hard shell of the seed protected the embryo within. The seed needed water so that it could become moist, open up and begin its process of germination. The plant sends out its roots that will bring nutrients to the rest of the plant. Each seed does not come from the same parents and so their rate of growth and end product will be different for each plant.

Relate Activity and Concept

11. Have the students create a bar graph of the growing plants. Along the Y axis have the students record the length of the roots in centimeters. Along the X axis have the students record each seed's daily growth.

12. Have students consider the following questions:
Which seed began to germinate first?
Did all the seeds of that kind germinate first?
Why do the roots look different on each seed type?
Why would a plant want to have long, short, thin, thick roots?