Recall that archaea and bacteria used to be grouped in the same category. how were archaeons first distinguished from other prokaryotes?

By difference in there ribosomal RNA sequence

Explanation:

Both bacteria and archaea lack membrane-bound nucleus and earlier both are considered in the same categories. Carl Woese was the scientist who discovered that bacteria and archaea are not similar.

Carl Woese and his lab members checked the ribosomal RNA in some archaeans and concluded that the archaeans are more closely related to eukaryotes than bacteria. After the study on archean Carl Woese classified the prokaryotes into two domains i.e., bacteria and archaea.  

Therefore by difference in the ribosomal RNA sequence archaeons first distinguished from other prokaryotes.

prophase: we can observe the chromosomes to coil up and condense. they become visible. nuclear membrane and envelope disintigrate.s

metaphase: chromosomes align at the center, the metaphase plate. spindle fibers attach to centromeres of the sister chromatids. they meet at kinetochores.

anaphase: sister chromatids are pulled towards each opposing centromere, set on different poles.

telophase: chromosomes are now clustered up only on either sides of the cell. nuclear membranes reform, and a new cell wall forms along the cell plate. this will lead to cytokinesis, the process that divides the cell membrane and forms the cell wall.