Final answer:
Cytokinesis is a phase in cell division that begins during late anaphase or early telophase. The cleavage furrow, a part of cytokinesis, begins at the onset of telophase, not after telophase is totally finished. The furrow is not made by the mitosis spindle but by a contractile ring.
Step-by-step explanation:
Cytokinesis is the phase of cell division where the cytoplasm of a cell is divided to form two daughter cells. Although the timings may overlap, it usually begins during the late stage of mitosis - either late anaphase or early telophase. Hence, it is true to say that cytokinesis usually begins in anaphase.
The cleavage furrow, which pinches in the cytoplasm, does not begin and end after telophase is totally finished. Instead, it typically starts appearing at the onset of telophase and reaches completion after nuclear division - during cytokinesis. The cleavage furrow is not made by the mitosis spindle. Rather, it is a result of a contractile ring composed mainly of actin and myosin in animal cells.
Therefore, the sentence 'Cytokinesis always begins and ends in telophase' is not entirely correct as cytokinesis commences before telophase ends and it concludes after telophase.
Learn more about Cytokinesis