Summer Research Program for Science Teachers
Jerry Snowhite
Brooklyn Technical High School
Cytoskeleton of a Cell
Reference: Scientific American, January 1998 (keyword: tensegrity) [Teaching Standard D- Make accessible science media]
GOAL: Build as tall a
structure as possible with the following materials: [9-12 Content Standard E- Abilities of technological design]
plastic straws, string, elastic string (found in sewing stores).
Teacher notes: the real goal is to explain the
cytoskeleton of a cell. [9-12 Content Standard C- The cell]
[Content Standard Unifying Concepts- Models and explanation]
· elastic string = Microfilaments (contractile elements)
· elastic string inside a straw = Microfilaments also because they get stiffer when they shorten.
· plastic straws = Microtubules (girders):
· string = Intermediate fibers (connect Microtubules and Microfilaments to each other, as well as to the surface membrane and the cell's nucleus; also act as guy wires to secure the nucleus)
Teacher notes: Parameters of realistic cells:
· Even before one of the structures or cell is subjected to an external force, all the structural members are already in tension or compression - they are prestressed.
· Pushing down flattens the model. As soon as the pressure is removed, the model springs back to its original roughly spherical shape.
· Linear stiffening: If you pull on a cell, the cell will become stiffer and stiffer.
Grading Rubric
¨ Stability
¨ Resilience:
¨ Aesthetics
¨ Creativity
¨ Elegance
¨ Humor
¨ Ability to work in groups
¨ Equal participation of all members.
¨ Documentation of your endeavors.
¨ Oral presentation of your work to class.
¨ Written report - yes! Neatness and spelling count. Yes! References are required.
Report
Things that you tried
Things that did not work out
Things that you learned
What would you do differently next time?
How could you apply the principles that you learned to other things?
[Teaching Standard B- Orchestrate scientific discourse]
What grade did you earn? WHY?
Comments
Bibliography and References