They will continue to diminish coastline and eventually coastline could disappear for japan
During metaphase 1, the spindle fibers attach to the centromeres of each chromosome. Both kinetochores of each sister chromatid pair are turned toward the same pole. And 2 members of each chromosome pair (sister chromatids) are pulled into each new cell during anaphase 1.
I think the answer you want is they are called chromatids.