The process of happens in the nucleus of Eukaryotic cells and happens in the Rough Endoplasmic Reticulum or the Ribosome of the cell.

it is called the mitotic spindle

the cell is the smallest structural and functional unit of living organisms, which can exist on its own. therefore, it is sometimes called the building block of life. some organisms, such as bacteria or yeast, are unicellular—consisting only of a single cell—while others, for instance, mammalians, are multicellular.