(i) Q-banding : It is obtained when chromosomes are stained with quinacrine mustard. It stains A- T rich area.
(ii) G-banding : Chromosomes are stained with Giemsa. It stains sulphur rich protein parts.
USE OF KARYOTYPING
(i) It suggests primitive or advanced features of an organism. If karyotype shows a large size difference between the smallest and the largest chromosome of the set and having fewer metacentric chromosomes is called assymetric karyotype, which is a relatively advance feature.
(ii) The karyotype of different species are compared and simillarities in them represent the evolutionary relationships.
(iii) Karyotype is helpfull in detection of chromosomal abberrations.
Diagrammatic representation of Karyotype. In idiogram chromosomes are arranged in decreasing order of size.
Sex chromosomes are placed in last but in idiogram of Drosophila sex chromosomes are placed first. Idiogram is specific for every species so it may be used in criminal investigation by forensic experts.