Anaphase — Definition & Diagrams

What's Anaphase in Mitosis?

Anaphase is the third phase of mitosis. It starts as soon as metaphase ends, and it comes right before telophase.

During anaphase, the chromosomes that are lined up in the center of the cell are pulled apart, separating the sister chromatids. The chromatids are pulled towards the centrosomes at opposite poles of the cell. Finally, the cell begins to elongate.

$$\color{#8925AE}{\text{Vocabulary Review:}}$$

$\color{#8925AE}{\text{Interphase}}$ : The longest part of the cell cycle where the cell grows and DNA is replicated to prepare for nuclear division

$\color{#8925AE}{\text{Nuclear Division}}$ : The process of dividing the nucleus

$\color{#8925AE}{\text{Mitosis}}$ : The process of dividing one nucleus into two identical nuclei. This occurs in all cells except for sex cells

$\color{#8925AE}{\text{Cytokinesis}}$ : The final step of cell division where the cytoplasm is divided to form daughter cells

$\color{#8925AE}{\text{Diploid Cell}}$ : Cell that contains two sets of chromosomes

What Happens After Metaphase?

In the previous phase, metaphase, the chromosomes lined up along the center of the cell. During anaphase, the centromeres of each chromosome split and the mitotic spindle pulls the sister chromatids apart. The chromatids of each chromosome are pulled to opposite ends of the cell. This way, there is a complete set of chromosomes on each side.

Remember:

Chromosomes in regular cells consist of one chromatid. Before mitosis takes place, the chromosomes are replicated. This is why each chromosome is now made up of two sister chromatids joined by a centromere. When the sister chromatids get pulled apart during anaphase, each one becomes a chromosome again.

The diagram below shows how this works.

(Video) Mitosis: Splitting Up Is Complicated

by CrashCourse

Anaphase is the third phase of mitosis. It happens between metaphase and telophase. In this step, each pair of chromosomes is separated into two identical chromosomes by motor proteins. Watch the video clip above to see this process in action.