The following points highlight the four main types of permanently specialized chromosomes. The types are: 1. Nucleolar Chromosomes 2. Sex Chromosomes 3. B Chromosomes 4. Chromosomes with Diffuse or Multiple Centromeric Regions. Permanently Specialized Chromosomes: Type # 1. Nucleolar Chromosomes: The chromosome forming the nucleolus (plural = nucleoli) is called the nucleolar chromosome. Normally one or more chromosomes in the [...]
The following points highlight the two main ways of representing chromosome set of species. The ways are: 1. Karyogram 2. Idiogram or Idiotype. Representing Chromosome: Way # 1. Karyogram: Photomicrographs of the chromosomes of a single representative somatic metaphase cell are clipped out and arranged in homologous pairs according to their size. If the chromosomes are small and there is [...]
In this article we will discuss about the molecular structure of centromere. Eukaryotic chromosomes possess a segregational device called centromere which is responsible for the chromosomc movement during cell division. Chromosome fragments without a centromere (acentric fragments) are unable to move to any of the poles during cell division; as a result, they are excluded from the daughter nuclei and [...]