system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How can spiders contain so much web when their body's are so small?
gpt
They make it themselves with their spinnerets. It's not like they have a storehouse of web inside their body. They have silk glands that create the web on demand.

The web itself weighs VERY little. One strand stretching across the entire Earth would weigh less than a bar of soap.