A karyotype is essentially a photograph of a cell's chromosomes taken through a microscope. Researchers set up a karyotype by using chemical solutions to halt a dividing cell in metaphase (when chromosomes are most condensed), then staining the chromosomes with dyes and taking micrograph photos. To display the karyotype, the chromosomes are grouped and numbered by size so the researchers can check for extra chromosomes, missing chromosomes, or other abnormalities. The adjacent image illustrates a normal human karyotype. HeLa cells, descended from the original cervical cancer cells of Henrietta Lacks, are unique in that they can vary widely in chromosome number. Defects in proteins that orchestrate cell division result in descendant cells with too many or too few chromosomes, one of the hallmarks of cancer cells. The karyotype that follows, originally published in 1989, shows all of the chromosomes in a single metaphase HeLa cell. Courtesy of Dr. Thomas Ried, NIH and the Association for Cancer Research/ National Human Genome Research Institute Compare the HeLa cell karyotype with the normal human karyotype, then answer the questions that follow. Courtesy of Dr. Thomas Ried, NIH and the Association for Cancer Research/ National Human Genome Research Institute Including the sex chromosomes, the chromosome number of a normal human cell is enter answer and the chromosome number of this HeLa cell is enter answer . (Hint: Chromosome number is different from total chromosome count.)

In a normal human karyotype, the typical chromosome number is 46. This includes 22 pairs of autosomes (non-sex chromosomes) and 1 pair of sex chromosomes (XX for females, XY for males).

For HeLa cells, which are derived from cancerous cells, chromosome number can vary significantly due to genetic instability. The specific chromosome number of a HeLa cell can vary depending on the specific cell line and its characteristics. However, HeLa cells commonly exhibit abnormal chromosome numbers, often with aneuploidy (an abnormal number of chromosomes). This can result in cells having more or fewer than the usual 46 chromosomes found in normal human cells.

To answer the question directly:

The chromosome number (including sex chromosomes) of a normal human cell is 46.

The chromosome number (including sex chromosomes) of the HeLa cell karyotype can vary widely but is typically abnormal compared to the normal human karyotype.

Since the exact chromosome number for the specific HeLa cell karyotype isn't provided in the text, we can state that HeLa cells often display abnormal chromosome numbers compared to normal human cells.