Question

polar bear have more fat inside his body . which tissue is responsible for this

Answer 1

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Bring Science Home
Bring Science Home
How Animals Stay Warm with Blubber
Explore blubber biology with Science Buddies

By Science Buddies on December 29, 2011
How Animals Stay Warm with Blubber
Credit: George Retseck

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Key concepts
Temperature
Heat transfer
Adaptation
Insulation
Fatty tissue

Introduction
Have you ever wondered how whales and other marine mammals survive and keep warm in the cold oceans? Warm-blooded mammals can live in these chilly conditions because their bodies have some cool warmth-saving adaptations, thanks to generations of natural selection.

In other words, to pass on characteristics (via their genes), the predecessors of modern marine mammals had to overcome different challenges to reproduce, and their descendants received the genes that allowed for their survival. This kind of change in organisms over time is what fuels evolution. An important adaptation for marine mammals is blubber, a thick, insulating layer of fat beneath the skin that helps to keep body warmth in and the cold of the air or water out. Will a layer of fake blubber—in the form of shortening—help you keep from getting cold?


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Background
Mammals that have evolved to live in cold waters, such as whales, seals, sea lions and polar bears, commonly have a layer of blubber. Whether they are living in cold waters near the North Pole or around Antarctica or are visiting the deep ocean, these animals' blubber is vital to their survival. During the winter, the air in the Arctic (the northernmost part of the world) is often below –40 degrees Celsius (–40 degrees Fahrenheit). Antarctica, the coldest place in the world, can be below –60 degrees C (–76 degrees F). Depending on the species, whales dive more than 400 or 500 meters (about one fourth of a mile) deep in the ocean, where the water can be colder than 12 degrees C (54 degrees F).

Blubber helps these marine mammals from getting too cold. (Cold-blooded marine animals, such as fish, sharks or crabs, do not need to stay warm and can let their body temperatures get closer to that of the water. Thus, they do not need to have this extra insulation.) Blubber is a thick layer of fat (adipose) tissue. Animals store extra digested food in the form of adipose tissue, which contains molecules called lipids. Adipose tissue has a relatively low thermal conductivity, which means that it does not transfer heat as well as other tissues and materials—such as muscle or skin. That way, it helps to insulate an animal's body.

Answer 2

The tissue responsible for the storage of fat in polar bear's body is adipose tissue.
Hope it helps you