View source for Prophase

This is the first of the 6 phases that make up the mitosis part of the [[Cell cycle|cell cycle]]. The other phases are prometaphase, [[Metaphase|metaphase]], [[Anaphase|anaphase]], telophase and [[Cytokinesis|cytokinesis]].&nbsp; 

In this phase replicated [[Chromosome|chromosomes]] consisting of two closely associated sister [[Chromatids|chromatids]] condense, with help from the condensin complex. Simultaneous to this, a mitotic spindle made up of microtubules assembles between two centrosomes which then migrate due to motor proteins to positions either side of the nuclear envelope. Microtubule activity is greatly increased in this period by γ-tubulin. Mitotic spindles are vital in the division of chromsomes and will attach to [[Kinetochore|kinetichores]] in prometaphase. 

Prophase ends with the breakdown of the [[Nuclear envelope|nuclear envelope]], allowing the spindle to attach to chromosomes in prometaphase. &nbsp; 

<references />1. Alberts, B et al (2002) Molecular Biology of the Cell (4th ed) New York: Garland Science