Final answer:
The 'C-banding' technique involves staining chromosomes to visualize banding patterns, identifying these bands along with chromosome size and centromere location, and arranging them to form a karyotype.
Step-by-step explanation:
The 'C-banding' technique is a cytogenetic method used to visualize the banding patterns of chromosomes in metaphase. This procedure begins with the stimulation of cell division in a sample, followed by application of a chemical like colchicine to arrest the chromosomes in metaphase. After treating the cells with a hypotonic solution to spread the chromosomes apart, the sample is fixed on a slide. The chromosomes are then stained using dyes, commonly Giemsa stain, to enhance the visibility of 400-800 bands formed by tightly coiled DNA and proteins. Once stained, chromosomes are viewed using bright-field microscopy. The patterns observed, along with the chromosome's size and centromere location, aid in distinguishing each chromosome pair. Geneticists can create a karyotype by photographing the chromosomes and arranging them into a visual depiction that aligns homologous chromosome pairs by size.