©Charles R. Downing. (1990, 1994). Cranial Creations in Life Science, J.Weston Walch Publishers, Inc.

The cell membrane can be analogous to a chain-link fence with gates patrolled by security guards. Some things are small enough (e.g. bugs and wind)to pass through the chain-link without the guard's assistance or even their knowledge (like diffusion of oxygen and carbon dioxide through the membrane). Other things go through the gates after "permission" from the guards (like proteins that must meet certain requirements of electrical charge to enter the cell). Still other things are carried into the cell by the guards (analogous to active transport in the cell).

1. Form work groups as instructed by your teacher.

2. Select a RUNNER/HOLDER to get the felt pens and paper, a WRITER to write down the analogy description for the back of your project, and a READER to read the description aloud at the end of the assignment.

3. Select your organelle from the list on the board and sign up for it with your teacher.

4. Using any piece of paper at least 24x36 inches, draw and color your own analogy for some specific cell part. On the back of the drawing, attach a brief explanation of your analogy. The explanation should be no more than one page in length.

5. You will have thirty (30) minutes to complete this art/analogy.

6. Each group will present their analogy to the class at the end of the 30 minute time period. The HOLDER and WRITER will hold the drawing for the class to see while the READER reads the description to the class.

7. Your group will receive a grade based on the appropriateness of the analogy.