How does the spider make the silk?
The thread is released through silk glands. Many species of spider have different glands for different jobs, such as housing and web construction, defense, capturing and detaining prey, mobility and in extreme cases even as food. Thus, the silk needs to be specialized for the task at hand so success is guaranteed. The gland’s visible, or external, part is termed the spinneret. Depending on the species, spiders will have any number of spinnerets, usually in pairs. The beginning of the gland is rich in sulfhydryl and tyrosine groups, the main ingredient to silk fiber. After this beginning process, the ampulla acts as a storage sac for the newly created fibers. From there, the spinning duct effectively removes water from the fiber and through fine channels also assists in its formation. Lipid secretions take place just at the end of the distal limb of the duct, and proceeds to the valve. The valve is believed to assist in rejoining broken fibers, acting much in the way of a helical pump.
