Final answer:
The Brooks Range is the mountain range that runs across northern Alaska, and it is part of the Spine of the Continent Wildway, extending from Alaska to Mexico.
Step-by-step explanation:
The mountain range that runs west to east across northern Alaska is the Brooks Range. This range is part of the Spine of the Continent Wildway, which extends from Alaska, through the Rocky Mountains, to the uplands of Western Mexico. The Brooks Range is a crucial part of this corridor, as it supports a diverse range of wildlife and ecosystems, including the boreal forest, which features a combination of low vegetation and tall conifers, and is often characterized by its stunning landscapes, such as the snowcapped peaks that define the region.