Lesson Overview
Brief Description of Lesson/Task/Activity: The concept of osmotic potential is difficult to grasp. Using this activity, students will be able to “see” how water moves based on differing concentrations of solutions. This activity will help students understand the process of osmosis and develop an understanding of sugar storage in different types of plants. The task also asks students the why of sugar storage and about the role of sugar (carbohydrates) in plants and animals. The task can be used while teaching homeostasis to solidify the concept of osmosis.
Time Frame: 5-7 days
Type of Differentiation for AIGs:
- Enrichment
- Extension
Adaptations for AIGs:
- Content
- Process
- Product
Explanation of How Resource is Appropriate for AIGs: This activity requires AIG students to address relationships between concepts, move beyond the regular curriculum, focus on process and skills, develop their own hypothesis and to reach their own conclusions, and be active learners.
Needed Resources/Materials:
- Computer with internet
- Sweet potatoes
- Distilled water
- Sucrose
- Beakers
- Knife
- Balance
- Stirring rod
- Calculator
Sources:
- http://www.chemteam.info/Solutions/Molarity.html
- http://www.teachertube.com/viewVideo.php?title=Calculating_Molarity&video_id=100749
Teacher Notes: Before assigning this activity, students need an intro to molarity and solution concentration. Students need to be able to understand that molarity is a measure of concentration (the number of moles of solute/liter of solvent), and that the higher the molarity, the more solute there is. Students need to know that moles are a measure of quantity. There are several videos/websites that explain molarity if you want the students to do independent study to learn about moles. Some websites are listed above. Students also need to know how to make a 1 M solution of sucrose and then create different dilutions of this to create a variety of different molarity solutions. Students will also need to be able to calculate percent mass lost or gained by the potato when placed in different molarity solutions.