Why is it that a fully developed potato can verbs to grow vines or roots and flowers? I put a store bought potato in a chalice of water....

I put a store bought potato in a chalice of water. I placed toothpicks contained by the potato and submerged one half. Within days tiny white roots sprouted out of the bottom and green vines come out of the top. Weeks later the chalice of water is gelatinous with white vines and three foot hight vines have shot out of the top and are garlanded with pink flowers. How is this possible?
Answers:    The simplest answer is that's how potatoes reproduce.The potato is the "seed" of the plant. You enjoy created an environment that they need to reproduce. It won't las too long, though. Once the nutrients within the potato are consumed by the plant, it will die.
Mother Nature provides food even for the birds =)

A fully developed potato or any bulb will become a seed for their continuation and survival.
Now that you know how to sprout a potato; you can split it within peaces keeping the white sprouted part intact, buy yourself a couple of 10+ gallon container, pack it with 50/50 percent dirt and compost, plant almost 2 rooted pieces in respectively container and watch them grow! Before you know, you'll be intake fresh harvested potatoes right from your porch, stern or front yard =)

Link below shows how to spawn compost with the stuff we throw within the barbage in anyways: