Blubber
A thick layer of vascularized adipose tissue under the skin of all cetaceans
Real World Example
Imagine trying to stay warm during a frigid winter day by bundling up in layers of clothing. Just like those layers of clothing trap heat to keep you warm, blubber acts as an insulating layer for cetaceans, such as whales and dolphins, in the cold ocean waters. The layers of clothing are like the blubber's vascularized adipose tissue, providing warmth and protection, while the cold air outside is akin to the chilly ocean environment these creatures navigate.
Practice Version
