--- title: The Arctic: ice, snow and the polar bear's world — a lesson of Mova's school · trees and pragmatics description: «The Arctic: ice, snow and the polar bear's world», a lesson of the biology course of Mova's primary school, sentence by sentence with dependency trees and pragmatics. It begins: The Arctic is the frozen top of the world: an ocean covered by floating sea ice, surrounded by the cold treeless land cal --- [Mova](https://md.mova.elamur.ai/free/en/) · [this page in HTML](https://mova.elamur.ai/free/en/corpora/school/biology/6-the-arctic/) [home](https://md.mova.elamur.ai/free/en/) / [corpora](https://md.mova.elamur.ai/free/en/corpora/) / [school](https://md.mova.elamur.ai/free/en/corpora/school/) / [Biology](https://md.mova.elamur.ai/free/en/corpora/school/biology/) / The Arctic: ice, snow and the polar be… # The Arctic: ice, snow and the polar bear's world Lesson 6 of the biology course of Mova's primary school: 17 sentences, each with its syntax tree and pragmatics. The lessons are written for Mova, and their agreed trees are part of Mova corpus 0.4 (CC BY-SA 4.0). How Mova does on its tests: [the lesson at school](https://md.mova.elamur.ai/free/en/school-run/biology/6-the-arctic/). - [0](https://md.mova.elamur.ai/free/en/corpora/school/biology/6-the-arctic/0/) — The Arctic is the frozen top of the world: an ocean covered by floating sea ice, surrounded by the cold treeless land called the tundra in the north of Europe, Asia and North America. - [2](https://md.mova.elamur.ai/free/en/corpora/school/biology/6-the-arctic/2/) — Arctic animals are built like thermos flasks: thick fur and fat, small ears, short legs and snouts, and tricks like sleeping under a bushy tail or living in tunnels under the snow blanket. - [3](https://md.mova.elamur.ai/free/en/corpora/school/biology/6-the-arctic/3/) — The polar bear is the king of the sea ice: it hunts seals from the ice edge, so as the world warms and the summer ice shrinks, it has less time to hunt. - [4](https://md.mova.elamur.ai/free/en/corpora/school/biology/6-the-arctic/4/) — In Frozen, Sven the reindeer begs for carrots; real reindeer dig through the snow with their broad hooves to eat lichen, and unlike other deer, both the males and the females grow antlers. - [5](https://md.mova.elamur.ai/free/en/corpora/school/biology/6-the-arctic/5/) — Polar bears hunt seals from the sea ice and swim well, kept warm by fat up to about 10 cm thick; their skin is black and their hairs are see-through, only looking white because they scatter the light, like snow does. - [6](https://md.mova.elamur.ai/free/en/corpora/school/biology/6-the-arctic/6/) — Polar bears are classed as marine mammals, and as Arctic sea ice shrinks in summer they have less time to hunt and must live longer on their fat. - [7](https://md.mova.elamur.ai/free/en/corpora/school/biology/6-the-arctic/7/) — The Arctic fox sleeps with its bushy tail over its nose, has small ears, short legs and very thick fur, and turns white in winter and brown or grey in summer, so it matches the snow or the bare ground. - [8](https://md.mova.elamur.ai/free/en/corpora/school/biology/6-the-arctic/8/) — Walruses use their tusks, up to about 1 metre long, to haul out onto ice and to show who is boss, and find clams on the seabed with sensitive whiskers. - [9](https://md.mova.elamur.ai/free/en/corpora/school/biology/6-the-arctic/9/) — Reindeer, called caribou in North America, have broad hooves for snow and ice, dig for lichen in winter, and their eyes change from gold in summer to blue in winter. - [10](https://md.mova.elamur.ai/free/en/corpora/school/biology/6-the-arctic/10/) — North of the Arctic Circle the sun does not set for weeks in midsummer and does not rise for weeks in midwinter, because the Earth is tilted. - [11](https://md.mova.elamur.ai/free/en/corpora/school/biology/6-the-arctic/11/) — Snowy owls often hunt in daylight on the tundra; one may eat more than 1,500 lemmings in a year, and they lay more eggs when lemmings are plentiful. - [12](https://md.mova.elamur.ai/free/en/corpora/school/biology/6-the-arctic/12/) — The male narwhal's tusk is a front tooth up to about 3 metres long that grows through its upper lip, and in the Middle Ages such tusks were sold as unicorn horns. - [13](https://md.mova.elamur.ai/free/en/corpora/school/biology/6-the-arctic/13/) — When wolves come, musk oxen form a ring with horns out and calves in the middle, and their woolly underfur, qiviut, is said to be about eight times warmer than sheep's wool. - [14](https://md.mova.elamur.ai/free/en/corpora/school/biology/6-the-arctic/14/) — The northern lights glow when tiny particles from the sun hit gases high in the air, mostly green from oxygen, and near Antarctica there are southern lights too. - [15](https://md.mova.elamur.ai/free/en/corpora/school/biology/6-the-arctic/15/) — Lemmings spend the winter in tunnels under the snow, which traps air like a blanket; the story that they jump off cliffs together is a myth helped by a faked 1958 film. - [16](https://md.mova.elamur.ai/free/en/corpora/school/biology/6-the-arctic/16/) — The bowhead whale can smash through ice about 60 cm thick with its head to make a hole to breathe, has blubber up to about 50 cm thick, and some are thought to have lived over 200 years. - [17](https://md.mova.elamur.ai/free/en/corpora/school/biology/6-the-arctic/17/) — Reindeer are the only deer in which both males and females usually grow antlers. - ← previous: [The desert: living with little water](https://md.mova.elamur.ai/free/en/corpora/school/biology/5-the-desert/) - next →: [Antarctica: penguins, seals and the coldest place on Earth](https://md.mova.elamur.ai/free/en/corpora/school/biology/7-antarctica/) - ↑ back to [Biology](https://md.mova.elamur.ai/free/en/corpora/school/biology/)