Model of the Atom (Niels Bohr). In 1913 one of Rutherford's students, Niels Bohr, proposed a model for the hydrogen atom that was consistent with Rutherford's model and yet also explained the spectrum of the hydrogen atom. The Bohr model was based on the following assumptions. 1.
Landforms. The Great Rift Valley is like a jagged scar on the face of Africa. It extends from South Africa, along the eastern region, and up to the Arabian Peninsula. The Great Rift Valley is a long line of escarpments that have been created by two tectonic plates drifting apart.
However, there are still a few areas where the characteristic vegetation zones of East African mountains can still be witnessed. In altitudes between 2000-3000m grows an alpine forest, between 2500-3300m follows the bamboo zone, which again is replaced by montane forests above 3500m.