What is the Eukaryotic Cell Cycle?

1 Answer
Oct 7, 2016

The eukaryotic cell cycle is the series of events a cell undergoes in order to duplicate its DNA and divide into two identical daughter cells.


The eukaryotic cell cycle is split into two parts: interphase and mitosis.

Interphase is split into three section:

  • #"G"_1# (Gap 1)
  • #"S"# (Synthesis)
  • #"G"_2# (Gap 2)

Knowledge of interphase is not really required, even at A-level, so I won't go into it here; all you need to know is that during interphase, the cell grows and duplicates its internal structures in preparation for mitosis.

Mitosis is split into three sections:

  • Prophase
  • Metaphase
  • Anaphase
  • Telophase

Since mitosis is a very long process, I will only go through a vague overview of it. But here is a video explaining it in detail. And here's an animation of it.

In prophase, the nuclear membrane and nucleolus dissolve, whilst the DNA condenses to form visible chromosomes, which are two sister chromatids attached at the centromere. The mitotic spindle also forms.

During metaphase, the mitotic spindle pulls each chromosome to the centre of the cell, and they each line up along the cell's equator.

During anaphase, the mitotic spindle elongates drawing the chromosomes to the ends of the cell. At this point, the sister chromatids are separated at the centromere. The elongation of the mitotic spindle also causes the cell to elongate.

During telophase, the nuclear membranes and nucleoli reform around the chromatids. The chromosomes also uncoil and loosen.

(Telophase is followed by cytokinesis where a cleavage furrow forms through the centre of the cell, which causes the cell to divide into two daughter cells.)