How many individual chromosomes (not pairs) does each cell in an individual with Down syndrome have?

An individual with Down syndrome typically has 47 chromosomes in total. This genetic condition usually arises from the presence of an extra copy of chromosome 21, a phenomenon known as trisomy 21. In normal human cells, there are 46 chromosomes, organized into 23 pairs. However, in the case of Down syndrome, the extra chromosome results in a total count of 47 individual chromosomes.

Thus, when considering the individual chromosomes, not pairs, each cell in an individual with Down syndrome contains that extra chromosome, leading to the total of 47. This understanding is crucial for recognizing how chromosomal abnormalities can lead to specific genetic conditions and their associated characteristics.