Which process or processes are responsible for the series of ice ages that occurred during the cenozoic era?

Glaciation and the Antarctic Circumpolar current

Explanation:

As the supercontinents continued to separate, cold water was easily transported around the globe through the Antarctic Circumpolar current. This assisted periodic glaciation during the Cenozoic Era, leading to a series of ice ages.

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.

the sphincter muscles at the end of the digestive tract is the anus.