If you know that you are not pregnant, how long is too long before you should be alarmed if you don't have your period? What could be the possible reasons for a delayed period?
WEATHER: The tundra is the coldest and the driest of all the biomes on Earth. There is very little rainfall in the tundra; it rains less than ten inches a year. Winters here are long, and summers short, sometimes they last for only 6 - 10 weeks. In the winter the temperature can reach -50Â°F (-45.5Â°C).
Tundra is the cold, treeless region around the poles that has permafrost as one of its defining features. Even at the height of summer, the soil a few centimetres under the surface remains frozen. The tundra therefore lacks animals that dig deep burrows and plants that require deep root systems. The permafrost, plus the short summer and seasonal waterlogging, also explains why trees don't grow here.