Lesson 1: Tour A Power Plant

SUBJECT: Science

OBJECTIVE: Students will learn the parts of the corn plant, and will be introduced to photosynthesis.

EVALUATION: Students will know that corn is a fast-growing, efficient "power" plant!

BACKGROUND FOR TEACHERS:

The corn plant is one of nature's most amazing energy-storing machines, a true "power" plant! It begins as a tiny seed weighing about one-hundredth of an ounce. In less than 10 weeks it grows into a plant seven to 10 feet tall! Then, in the next two months, it produces 500 to 1000 seeds similar to the one from which it started.

It does this by building a large, efficient energy "factory," a factory built of roots, leaves, stalks, and flowering parts. Think of a cornfield as a manufacturing community, with up to 35,000 factories per acre!

The raw materials are water, minerals from the soil, and carbon dioxide from the air. The power is sunlight. It runs the machinery that turns these raw materials into useful products. The process is called photosynthesis. It is a chemical reaction in which water + light + organic compounds (such as carbon dioxide) = organic compounds (such as sugar) + oxygen.

The products are kernels of stored energy. They consist of combinations of carbohydrates, proteins, oils and minerals. See Units 6 , 7 , and 9 for more information on the diversity of products!

STUDENT ACTIVITIES:

1. Ask students to read the story Claire Plays Basketball, then ask them to share at least three things they have learned about corn plants. (For example: The corn plant has 16-18 leaves when it is mature. The growing point is protected inside the whorl of leaves when the plant is young. The leaves angle upwards so they can absorb sunlight and help the plant manufacture sugar. Corn plants can grow taller than six feet, six inches. The ear always has an even number of rows, usually 14-16. There are usually 40-50 kernels in every row.)
   
   
2. Identify the parts of the corn plant in the worksheets. (Worksheet 1, 2, 3)
   
   
3. Encourage older students to dissect actual corn plants, as illustrated. (Worksheet 4)
   
   
4. This handout has detailed information on photosynthesis. Younger students will enjoy coloring the picture. Use the arrows to point out which factors go into corn (carbon dioxide + water + sunlight) and which products (oxygen + sugars or cellulose) are made by corn. (Worksheet 5)
   
   Older students can begin to appreciate the fact that, through the process of photosynthesis, corn is able to remove carbon dioxide, a pollutant, from the air, and replace it with oxygen, which we need to live. More information on this, particularly on ethanol, is available in Unit 7, Lessons 1, 2, and 3.
   
   
5. Encourage students to complete other activities related to corn anatomy! Corn roots are diagramed and studied in Unit 2, Lesson 2. Corn kernels are dissected and studied in Unit 9, Lesson 2.

Last reviewed May 7, 2004