G2 Phase (The second gap of DNA Synthesis)

The period after DNA synthesis, but before the next cell division is the G2 Phase. In this phase the cell prepares itself for mitosis by synthesizing essential proteins mainly for the production of spindle fibers......

Mitosis

A type of cell division in which a cell divides in to daughter cells each with the same number of chromosomes as was present in parent cell.

Mitosis, in eukaryotic cells, consists two phases majorly i.e. Karyokinesis Nuclear cell division) and cytokinesis (cytoplasmic division). These two process usually occur together.

Mitosis occurs exclusively in eukaryotes. For convince metaphase, anaphase and telephone.

Stryctre of Chromosomes

During most of the life of eukaryotic cell, the nucleus contains darkly coloured. Thread like (extended form) structure called chromatin (Greek word for colour). This chromatin is actually a long molecules of DNA, continuous from end to end, complexed with special protein called histones. But when cell divides, chromatins condense to form chromosomes (Greek cord coloured bodies). Most chromosomes consist of two arms (Jelomer with one arm)that extend out from a specialized region called the Centromere (meaning middle body).

Before a cell divides, it duplicates its chromosomes. The two remain attached at their Centromeres. As long as they are attached to one another, the copies are called sister Chromatids. Each Chromatid is a single DNA molecule identical to the DNA of the original chromosomes before replication. The whole structure (two sister Chromatids attach at their Centromere is still considered to be a single chromosomes.

During cell division the whole sister Chromatids separate, with each Chromatid becoming an independent daughter chromosome.