Subject:

Science

Grade:

9-12

ICLE Standards:

• Interpersonal - work to satisfy customer's expectations
• Informational - interpret and communicate information
• Speaking - organize ideas and communicate orally

Performance Task:

Wanda is a senior studying cosmetology, who plans to continue her studies next year at a community college.  Recently, while Wanda was doing on-the-job training, a customer commented to her how anxious she was concerning the affect the aging process was having on her skin. She bemoaned that her skin was beginning to lose some of its youthful characteristics, such as elasticity. The customer asked Wanda if she had any miracles or suggestions on skin care. Wanda said that she was not licensed yet as a cosmetologist but she did remember one thing from biology class that might be helpful. She suggested that the customer drink plenty of liquids, particularly water, to help maintain healthy skin.  Wanda's customer listened very intensely as she explained how important it was to keep body tissues hydrated to help the skin look healthier. Wanda further explained in simple terms the scientific principle that supported her suggestion. 

The customer was so impressed with Wanda's explanation that she invited Wanda and her teacher to speak on this issue at the Ladies Every-Other-Wednesday Club. Wanda accepted the invitation. She decided to use illustrations of a biology lab activity she completed demonstrating the principle of osmosis. 

Complete a lab investigation to demonstrate the osmosis of water through a semi-permeable membrane. Draw conclusions on the data and orally relate an application of the scientific principle.

Procedure:

1. Label one beaker A, another B, and the third C.

2. Fill beaker A with 100% water, beaker B with 95% water and 5% sucrose solution, and beaker C with 80% water and 20% sucrose solution.

3. Tie a knot at one end of each piece of cellulose tubing.

4. Open the remaining end of each piece of tubing.

5. Pour 95% water and 5% sucrose solution into each cellulose tube to within 5 cm from the top.

6. Pinch the top of a cellulose tube and place it in beaker A.  Fasten the tube to the beaker with a rubber band.

7. Repeat step six for beakers B and C.

8. Draw an illustration of each beaker after you have placed the filled cellulose tubes in the beakers.

9. Allow the tubes to remain in the solution for about twenty-four hours.

10. Draw an illustration of your results and note any changes in the shape and condition (felicity) of each piece of tubing.

11. Explain how the result in beaker C is comparable to the dehydration of skin cells under certain conditions. Speculate on some conditions that may cause this to happen.

12. Explain how the results in beaker A are comparable to the hydration of skin cells under certain conditions. Speculate on how these conditions may improve the quality of the skin.

13. Make a 10-minute persuasive presentation on the importance of drinking plenty of liquids.

14. Materials needed: 

• Three pieces of cellulose tubing, 20 cm lengths

• 95% water, 5% sucrose solution

• 80% water, 20% sucrose solution

• 100% water

• 150 ml beakers
  
  Water passes through a selective permeable membrane from an area of high concentration to an area of low concentration.

Knowledge / Skills:

Understand the transport (absorption and circulation) of materials throughout the body and related disorders such as high blood pressure, leukemia, anemia, and coronary thrombosis.  S.39

Know and apply the principles of scientific inquiry.  (Implicit in this statement are the processes of prediction, estimation, developing hypotheses, drawing conclusions, evaluation, and following ethical principles and professional procedures.)  S.114

Plan and apply real or hypothetical models and constructions to facilitate investigation and learning and the solution to practical problems..    S.115

Follow written directions carefully and accurately.  ELA.6

Prepare and deliver individual speeches by gathering information, rehearsing, making eye contact, speaking loudly enough, delivering information in a well-organized fashion, and appealing to the needs of the target audience.  ELA.10

Rubric:

3 The student followed the directions completely and was able to complete a confirmation investigation with almost no coaching. He or she could make observations and demonstrate a full understanding of the principle of osmosis. The student could draw conclusions and apply the scientific principle to skin care.

2 The student followed the directions and could complete a confirmation investigation with some help. He or she, with coaching, could make observations and could demonstrate an understanding of the principle of osmosis.  The student was able, after re-teaching, to see the application of the scientific principle as related to skin cells.

1 The student demonstrated little understanding of the principle with considerable coaching, re-teaching, extra help, and extended time to complete assignments.  He or she was not able to see the connection between the scientific principle and its application to skin cells.

0 The student did not follow the procedures or complete the task.  He or she could not make any conclusions.

Oral Presentation

4 POINTS:  The student introduced the subject and gained the attention of the audience using an effective set-up technique.  The body of the presentation included the main ideas and supporting evidence by using neatly prepared and understandable illustrations of the experiment.  The conclusion left the audience with a clear message concerning the hydration of skin cells as an application of the principle of osmosis.

3 POINTS:  The student was not effective in one component of the speech (introduction, body, conclusion).  However, the audience seemed to understand the message presented and the answers to clarification questions at the end of the speech.

2 POINTS:  The student was not effective in two or more of the components of the speech.  The audience seemed confused concerning the presenter's perception of the application of the scientific principle.

1  POINT:   The student did not make a presentation.

Keywords:

CHEMISTRY
LAB EXPERIMENTS

LIFE SCIENCE
HUMAN BODY
SCIENTIFIC INQUIRY
TISSUE
OSMOSIS
ORAL PRESENTATION
DIRECTIONS

Grades:

Kg [] - 1 [] - 2 [] - 3 [] - 4 [] - 5 [] - 6 [] - 7 [] - 8 [] - 9 [x] - 10 [x] - 11 [x] - 12 [x]

ICLE Application:

D

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