Final answer:
Karyotypes are commonly prepared from cultures of blood cells. The cells are collected from a blood sample or other tissue and stimulated to divide, allowing the analysis of chromosomes and identification of chromosomal abnormalities.
Step-by-step explanation:
Karyotypes are commonly prepared from cultures of blood cells. To observe an individual's karyotype, a person's cells (such as white blood cells) are first collected from a blood sample or other tissue. The cells are then stimulated to divide and the chromosomes are analyzed, allowing the identification of chromosomal abnormalities.