CELL DIVISION mit

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Mitosis in Root Meristems : 

Mitosis in Root Meristems Interphase in Onion Root Tip Cells. X 1000   This mitotic stage is characterised by intact nuclei containing one or more nucleoli and surrounded by an envelope.  Growth phase 1 (G1), growth phase 2 (G2) and the synthesis (S) phase occur during this stage of division.

Mitosis in Root Meristems : 

Mitosis in Root Meristems Early Prophase in Onion Root Tip Cells. X 1000   This mitotic stage is characterised by the breakdown of the nuclear envelope and condensation of chromatin.

Mitosis in Root Meristems : 

Mitosis in Root Meristems Late Prophase in Onion Root Tip Cells. X 1000    This stage is characterised by condensed chromosomes and the absence of a nuclear envelope. The spindle fibres are present at this stage, but are not visible in this illustration.

Mitosis in Root Meristems : 

Mitosis in Root Meristems Metaphase in Onion Root Tip Cells. X 1000   This stage is characterised by alignment of chromosomes (each consisting of two sister chromatids) along the metaphase plate.

Mitosis in Root Meristems : 

Mitosis in Root Meristems Anaphase in Onion Root Tip Cells. X 1000   This stage is characterised by the separation of sister chromatids which slide along the microtubules towards the poles of the cell.

Mitosis in Root Meristems : 

Mitosis in Root Meristems Early Telophase in Onion Root Tip Cells. X 1000   This stage is characterised by disassembly of the spindle apparatus and formation of a cell plate in the centre of the cell.  In animal cells, a cleavage furrow rather than a cell plate is formed.

Mitosis in Root Meristems : 

Mitosis in Root Meristems Late Telophase in onion root tip cells. X 1000   This stage is characterised by the reformation of a nuclear envelope and decondensation of chromosomes.  Cytokinesis occurs at the end of this phase and marks the final phase of division.

Mitosis in Root Meristems : 

Mitosis in Root Meristems Formation of Daughter Cells in Onion Root Tips. X 1000   This image illustrates the final stage of mitosis and the beginning of interphase.  Note the prominant cell plate forming between the condensing nuclei and beginning the separation of daughter cells.