Spider silk is a fiber that is spun by spiders, and although seven types of silk can be made, no spider is able to make them all. The silk is actually a protein made from amino acids called glycine and alanine, and each particular type of silk is used for different purposes. Dragline and minor silk typically are a smoother texture and are used for building webs, and attachment silk is used as an anchor. Other types of spider silk are sticky and used for trapping prey. These include the viscid and glue-like silks. Wrapping silk is used to secure freshly capture prey, and cocoon silk is used by female spiders to create a safe area for their eggs or hatched offspring.
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