Notochord, a flexible supporting rod along the back of an animal. It is present in all chordate animals at some stage in their development. A primitive chordate retains it throughout life. In higher vertebrate animals, the notochord is replaced before birth by a backbone.
Notochord
You Might Also Like
5 Most Cloned Animals
Sure you know about Dolly, but what about Snuppy and CC? They're not all magazine cover models, but they are notable clones. What are the five go-to species that scientists clone?
10 Things to Pack When Traveling with a Pet
When you're packing for a trip, you don't leave home without clean socks and toothpaste. But if you're bringing your pet with you, what essentials will it need? We've got 10 must-have items for your four-legged, furry friend.