Doubled chromosomes are held together by what

Something called "Sister Chromatids". They are held together by proteins at a region of the chromosome called the centromere. 

They're held together by the centromere.

Ifound this on google “interphase is divided into three phases: g1, s, and g2. the subsequent mitotic (m) phase consists of two processes: mitosis, the process of nuclear division, and cytokinesis, division of the cell's cytoplasm. each mitotic phase results in the formation of two cells that are genetically identical to the parent. for more information go to the web down below cyberbridge.mcb.harvard.edu › mitosis_3i hope this you for what your looking for.can you plz mark me brainliest?