The effect of cobalt on the structure of chromosomes and on the mitosis

Summary Cobalt exerts an effect on the structure of chromosomes and on the course and intensity of cell division in root tips of Vicia faba is.Despiralisation of chromosomes and an increase of the viscosity of the matrix substance causing stickiness of the chromosomes are induced by the treatment with cobalt.A cytostatic effect of cobalt was observed. The intensity of cell division is strikingly reduced after treatment with cobalt. Cobalt inhibits the passage of interphase cells into prophase so that this element can be considered to be a preprophase poison.