Is there one centomere for the two chromatids in a dyad?
Each chromatid has a centRomere. A chromosome is a pair of sister chromatids (general term)... also known as a dyad in meiosis. Tetrads are the precursors to separated dyads in meiosis. Having centromeres is super important for being able to pass down genetic information in eukaryotic cells. Prokaryotes and archaea have similar structures to physically keep track of their DNA.