AP BIOLOGY

Detailed explanation-1: -If colchicine is given to an animal or added to a culture of cells, all the cells beginning mitosis after the treatment will be arrested in the metaphase stage.

Detailed explanation-2: -Colchicine is a classical anti-mitotic drug which blocks mitotic cells in metaphase.

Detailed explanation-3: -Since colchicines inhibits growth of spindle fibres and the major role of spindle fibre is to pull the chromosomes to the poles during anaphase. So, colchicines treated cells will enter in cell cycle but will be arrested at metaphase.

Detailed explanation-4: -At a cellular level, colchicine is an antimitotic agent that inhibits mitosis by preventing the polymerization of tubulin, 11, 12 a constituent microtubule protein, thereby disturbing those processes dependent on microtubule function such as cell motility, intracellular movement, cell polarity, and mitosis.

Detailed explanation-5: -T h e arrest of mitosis at metaphase The most striking effect of cold and of colchicine is the arrest of mitosis when the chromosomes have reached metaphase spiralization. This arrest leads to an accumulation of cells at this stage.