system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5:How do animal detach themselves from their umbilical cord?
gpt
The umbilical cord connects the newborn animal to the placenta, which is an organ that attaches to the mother's uterus and is the channel through which nutrients flow to the embryo as it grows in the uterus. The placenta is expelled from the mother immediately after birth, and each animal has a separate one. Most animal mothers will eat the placenta, which is very rich in nutrients, severing it from the umbilical cord in the process. The rest of the cord will dry up and fall off in a few days on its own. The umbilical cord has no nerves, so the severing, drying and falling off do not cause any pain.