Homework 3 – Due 2 weeks after reception. (March 25) March 16, 2004

1. What factor is mainly responsible for the mechanical properties of elastin? (Name the specific amino acids responsible for this behavior).

2. Describe the basic levels of structure of collagen.

3. Briefly contrast and compare the structures of articular cartilage and tendon.

4. Explain the term “stress softening” and describe for what materials it should apply.

5. Contrast and compare the fibrous structures formed with (a) proteins and (b) polysaccharides.

6. What are the possible structural arrangements that lead to R-curve behavior in materials?

7. How would you measure the toughness of the mesogloea of a sea anemone, e.g., the Metridium senile (see page 21 of text)? Is it possible? How? Why or why not?