All organisms as hypothetically asserted by the cell theory states that all species that roams the earth is made up of cell/s. One-celled organisms are called prokaryoties while the multiple-celled organisms are called the eukaryotes.
Cell in definition is the simplest foundation and framework of every lingering specie in the biosphere.
The chromosome theory of inheritance, or the idea that genes are located on chromosomes, was proposed based on experiments by Thomas Hunt Morgan using Drosophila melanogaster, or fruit flies.
