The stage at which morphology of chromosomes is easily studied is the stage during which
Spindle fibres attach to kinetochores of chromosomes
Metaphase is the stage at which morphology of chromosomes is most easily studied. Chromosomes are condensed (thickened) and highly coiled in metaphase, which makes them most suitable for visual analysis. The spindle fibres attach to kinetochores of chromosomes during this stage.
Nucleolus, Golgi complex and ER reform at the Telophase.
Centromeres split and chromatids separate at the Anaphase.
DNA duplicates during the S-phase