Agnatha

High school (ages 12+)
Animals & Nature

Name:

Date:

Step 1 · Read the article

Open the article and read it at the level above. Then answer the questions below in your own words.

https://smallwhale.org/articles/agnatha

Write what each word means, using the article.

Do not copy the article. Write two things you learned, the way you would explain them to a friend.

Answers below are taken from the article’s stored facts, so they match what the student read.

1. What are Agnatha and why are they called "jawless fish"?Agnatha were the first fish that lived a long time ago. They didn't have jaws, so they sucked or rasped food instead of biting. They were the earliest vertebrates with a backbone and a nervous system.
2. How did Agnatha move without jaws or paired fins?Without paired pectoral or pelvic fins, Agnatha swam by undulating their bodies and using their tail fin for thrust. This helped them glide through both fresh and saltwater.

Gnathostomes: Vertebrates possessing jaws, a group that includes cartilaginous fishes, bony fishes, amphibians, reptiles, birds, and mammals.
Ostracoderms: An extinct group of armored, jawless fish from the Paleozoic Era, representing early vertebrate radiation.
Paraphyletic: A group of organisms that includes a common ancestor but not all of its descendants.
Trophic Levels: The position an organism occupies in a food chain, indicating its source of energy and its role in energy transfer.