Biology 8th Edition by Kenneth Mason ,Jonathan Losos,Susan Singer,Peter Raven,George Johnson

Exercise 10

Spider webs are made of "silk," which is a long, fi brous protein.The threads you see in a web are actually composed of manyindividual proteins. One important structural motif within spider's silk protein is a "β-crystal". β-Crystals are regions where the β-pleated sheets from the multiple individual protein fibers stack one upon the other. What chemical bonds are required for the formation of the β-crystals What level of protein structure is responsible for the formation of the silk you see in the web Predict how the presence of the β-crystal motif would influence the physical properties of the silk protein.