Following DNA condensation and mitosis, a cell's chromosome number and compacted structure, its karyotype, can be observed. Specific stains, like Giemsa, are used to reveal distinctive banding patterns, almost like miniature barcodes. The complete map, an individual's karyogram, is assembled and organized by size. In humans, from the largest, number one, to smallest, number 22, plus the 23rd pair, the sex chromosomes. This layout allows for the detection of chromosomal abnormalities like an extra copy. Within a chromosome, staining can also highlight different features along the arms. For instance, regions, the specific cytogenetic bands, are labeled based on their position from the centromere to the telomere. Counting outward, the short arm is designated with the letter p for petite, while the longer arm is denoted with the letter q for queue. This numbering scheme provides a way to pinpoint locations of genes for further study into related diseases and disorders.