It is during the prophase when chromatids become visible. Prophase is the first as well as the longest stage of mitosis.
I think that it is either metaphase or anaphase
metaphase
Chromatids are visible during the Prophase of the Cell Cycle, as the chromosomes which chromatids are formed from condense, thus making them visible.
Interphase.
Anaphase is the stage of mitosis when chromosomes split apart.
Anaphase is when the chromosomes are pulled to the opposite poles in the cell.
It depends on your level of study. Some courses will teach "prometaphase" while others will just go straight to "metaphase". Of course, the stages don't really exist in nature - it's one process. We try to divide up and organize mitosis, so there can be a discrepancy.
Chromatids are visible during the Prophase of the Cell Cycle, as the chromosomes which chromatids are formed from condense, thus making them visible.
Chromatids split during Anaphase.
Metaphase
The centrioles and asters are visible in the mid-prophase stage of mitosis.
Two chromatids are present in a chromosome at the beginning of mitosis.
metaphase.
Prophase. Prophase occurs directly after the G2 phase of interphase. In early Prophase, the sister chromatids condense further, becoming visible with a microscope.
According to Biologists, one of the features of the mitosis cycle includes the anaphase stage where sister chromatids tend to separate.
prophase
SIster chromatids move to opposite poles of the cell when the spindle fibres contract, pulling them apart. This occurs during the stage in mitosis known as anaphase.
During Mitosis, the spindle pulls apart the sister chromatids of the chromosome in the Anaphase stage.
Anaphase is the stage of mitosis when chromosomes split apart.