system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: When a worm gets split in two, how do both halves remain alive and seemingly react to things?

I was fishing today (using nightcrawlers as bait) and the question came to mind. Sorry if it's worded poorly.
gpt
In the long term, a bisected earthworm won't survive to make two new worms (although flatworms like planaria can survive being chopped into bits). An earthworm has a heart and a brain and other necessary organs up near the front.

In the short term, muscles and nerves can continue to function for quite some time after being removed from the rest of an organism. A fresh fish fillet- with no blood, bones, just muscle completely removed from the rest of the fish- can twitch for hours after the fish is killed. Until the individual muscle and nerve cells actually die they can still do their job, and nerves can randomly fire a signal to a muscle cell to contract as various chemical reactions occur in the nerve and tissue.