Theory:

Animals that live in extreme climate (hot or cold) possess special features to protect from such conditions. Importantly, these adaptations present in animals help them accustom to that particular habitat they live in.
Adaptation of animal present in polar region:
The polar region display extreme cold climates as they covered with snow for most time of the year. In this region, the sun does not set for six months, and in another six months, it does not rise. As a result of this, the temperature of the region may go as low as \(-37°C\) during the winter season.
 
Adaptations in polar bear:
 
1. White fur blends with the snow and thus helps to escape from predators. It is also used for catching prey.
 
2. Two thick layers of fur that protect from the extreme cold. Beneath the fur, there is a fat coat which acts as an insulator during the extreme cold.
 
3. Polar bears are good swimmers with wide and large paws that aids in swimming. Curved and sharp claws help the bear to walk on the snow easily.
 
4. While swimming, the nostrils remain closed.
 
5. Polar bears have strong sense of smell so they can easily catch the prey. Along with, the polar bear possess small ears to keep minimum body surface area to reduce the heat loss from the body.
 
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Polar bear
 
Adaptation in Penguins:
 
1. Penguins are flightless birds that also have white on their abdomen, which helps them merge with the region.
 
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Penguin
 
2. Thick skin and thick layer of fat that protects and insulates from cold.
  
3. They have streamlined body, flipper-like wings, and webbed feet to aid in swimming. It helps the penguin to catch their prey.
  
4. They huddle together to keep themselves warm.
 
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Penguins
Important!
In Jurong Birds Park, Singapore, Penguins are kept in big glass cases wherein icebergs are placed. The park's temperature is maintained at \(0\)\(° C\) and below.
However, when an animal is shifted from one habitat to another, they may not survive well. This is because the animal's body features are adapted to their natural habitat. They might have difficulties along with the new condition, and most of them cannot perish. 
Reference:
https://pixabay.com/it/photos/pinguini-imperatore-pinguino-bambino-429128/