I WONDER - What Are Jellyfish Made Of?

Jellyfish are predators of smaller sea creatures but are mostly composed of water. They lack a brain and heart, controlling their bodies through a simple nervous system. Without blood, they don't need a heart to pump it. Their thin skin allows them to absorb oxygen directly, eliminating the need for lungs.

How do jellyfish absorb oxygen?

What is unique about the skin of jellyfish?