Cell Cycle 

Cell Cycle is the process by which a cell and its contents
divide, to give rise to two daughter cells and this process is known as
mitosis.

 The Cell Cycle describes the different phases through which the cell
divides. Cell cycle occurs through 4 different phases. These are

 The two major events occurs during cell cycle is the DNA
synthesis and the chromosome segregation. DNA synthesis occurs in the S-Phase
of the cell cycle; in this step the entire DNA (genetic content) of the cell is
replicated. In M-phase or the mitotic phase chromosome segregates.

Between the S-Phase and M-Phase there are two checkpoints or
Gap Phases namely G1 and G2 Phases. These are the checkpoints or error check
phases where the cell confirms the proper replication of the DNA and the energy
requirements are met to proceed to the next phase.

Cell Cycle – S-Phase

The major events that occur in the S-Phase or Synthesis
phase of the cell cycle are

 DNA replicates and gives rise to chromatids and a pair of
chromatids are called sister chromatids, these are held together by a protein
called cohesin and the process is called as sister chromatid cohesion.

Cell Cycle – M – Phase

After the DNA replication process, the cell enters the
checkpoint G2 Gap Phase, where necessary error checks are done and proceeds for
the M – Phase or the mitosis phase. During the M-Phase the sister chromatids
moves to the poles of the cells and the cell divides. Each daughter cell
receives the identical genetic material.

Mitosis Phase –
Overview

Mitosis Phase of cell cycle occurs through 4 different
phases:

Prophase – Key Events

• Chromosome Condensation
• Nuclear Membrane Breaks
• Microtubule organizers moves to the poles

Metaphase –  Key Events

• Attachment of Microtubule to the centromere
• Chromosomes are arranged to the center of the cell

Anaphase –  Key Events

• Microtubules pulls the chromatids to the poles

Telophase –  Key Events

• Nuclear membrane formation around the chromosomes