The below mentioned article provides notes on colchicine. In 1937 O.G. Eigsti first succeeded in inducing tetraploidy in cells of onion root tips by the chemical colchicine. This is an alkaloid obtained from the seed and corm of liliaceous plant Colchicum autumnale. In high concentrations the drug is highly toxic to cells. If used in concentrations as low as 0.01% [...]
The following points highlight the two main causes of ploids. The causes are: 1. Aneuploidy 2. Euploidy. Ploids: Cause # 1. Aneuploidy: The individuals carrying chrornosome numbers other than somatic or diploid (2n), which are not true multiples of basic chromosome number or genome are called heteroploids or aneuploids. Thus aneuploidy results due to an addition of loss of less [...]
In this article we will discuss about the Variations in Chromosome Number to Plant and Animal. Every cell in the body of living organism is provided with a packet of genetic material (the nucleus) which contains chromosomes. The number of chromosomes in the nuclei of a given species is fixed. Some species of plants and animals have identical chromosome numbers. [...]