A veterinary research lab is analyzing canine tumor cells to map their chromosomal abnormalities.
During the preparation of a mitotic chromosome spread, the tumor cells were incubated in a dilute salt solution with a higher (less negative) water potential than the cytoplasm of the cells. Explain two steps in the process of how this incubation helps to separate the chromosomes from one another without causing cell lysis.
The resulting chromosomes are aligned and paired up to produce a karyotype. What is meant by a homologous pair of chromosomes?
Contrast the arrangement of eukaryotic DNA in this chromosome spread with the arrangement of DNA in prokaryotic cells by giving two structural differences.