Non-mosaic Down syndrome is a genetic disorder. Most people with non-mosaic Down syndrome have three copies of chromosome 21 in all of their cells (chromosome 21 trisomy); some have an extra copy of chromosome 21 attached to a different chromosome in all of their cells (chromosome 21 translocation).
Making the world better, one answer at a time. Stanislao Cannizzaro, an Italian chemist who worked with Dmitri, inspired Dmitri Mendeleev to come up with his creative ideas. Atomic Weight also inspired Mendeleev.
Mendeleev's Periodic Table. Original Russian Version Mendeleev is credited with creating the first real periodic table of the elements, where trends (periodicity) could be seen when the elements were ordered according to atomic weight. See the ? and blank spaces? Those are where elements were predicted.