Answer to Question 1
ANSWER: The polar jet stream forms in the North and in response to temperature contrasts along the polar front. It is situated at a lower altitude of about 10 km (33,000 ft), near the polar front, than the subtropical jet stream.
Answer to Question 2
ANSWER: The ultimate cause of jet streams is the energy imbalance that exists between high and low latitudes. In more detail, the polar front is a boundary separating cold polar air to the north from warm subtropical air to the south, and the greatest contrast in air temperature occurs along the frontal zone. This rapid change in temperature produces a rapid change in pressure. The sudden change in pressure along the front sets up a steep pressure (contour) gradient that intensifies the wind speed and causes the jet stream.
The transcription of three different genes that are found in the same chromosome.
An example of polymorphism: the two colour variations found in the orchid Dactylorhiza sambucina.
Magnetosomes found in the spirillum Magnetospirillum magnetotacticum.
Some of the many small molecules found in cells
A Steep-Gradient Stream
Different types of fog found throughout the United States