?the fat layer under a polar bear's skin

A) atom
B) cell
C) organ system
D) population
E) community
F) ecosystem
G) ?emergent property
H) ?tissue

Fat Layer

A layer in the body composed primarily of adipose tissue, which stores energy and insulates and cushions the body.

Polar Bear's Skin

The black skin of a polar bear, hidden beneath its transparent, hollow fur, which helps in absorbing sunlight to keep the bear warm in cold environments.

Tissue

In multicelled organisms, specialized cells organized in a pattern that allows them to perform a collective function.