Flocke, as zoo keepers have unofficially named the cub, was rescued by zookeepers after her mother, Vera, showed signs of rejecting her.
Vera was born in a Moscow zoo in 2002, and was sent to Germany when she was two years old.
The zoo's last surviving polar bear cub was removed from her mother's care on January 9 due to fears that she might follow the fate of two other tiny cubs eaten by another polar bear mother, Vilma, several days earlier.
The story has similarities with the story of Knut, a male polar bear cub from a Berlin zoo who was also abandoned by his mother, a 20-year-old ex-circus bear, Tosca, shortly after his birth in December 2006.
Knut quickly became a symbol of Germany's campaign against global warming and even Chancellor Angela Merkel recently admitted her fondness for the bear.
The polar bear's official logo has earned over $14 million for the Berlin Zoo and has been used on a wide range of merchandise, including cuddly toys, books, CDs, credit cards and souvenirs.
In Nuremberg, meanwhile, the five-week-old female cub opened her eyes on Tuesday, and her first milk teeth started to poke out. She is currently being bottle-fed with milk every four hours, and already weighs almost three kilograms (6.6 lbs).
The Nuremberg cub has quickly won the sympathy of millions of Germans and proposals on what to officially call the white fur ball have already begun flooding in.
The zoo has already received a total of 26,000 ideas from different parts of the world, including the U.S. and New Zealand. Most of them suggest traditional German female names - Gerda, Franka, Paula, and Berbel (short of Barbara).
The cub's new name will be announced by a special jury on Friday.
