What does a karyotype display?

A karyotype is a visual representation of an organism's complete set of chromosomes, typically obtained from a sample of blood or skin. This process involves staining the chromosomes to produce a distinct pattern, allowing for the examination of their number, size, and shape. Karyotyping is primarily used to diagnose chromosomal abnormalities, such as Down syndrome or Turner syndrome, by comparing the observed karyotype to the normal chromosomal count and structure expected for a species.

The focus of a karyotype is on the chromosomal makeup rather than the genetic sequences, biochemical pathways, or gene expression patterns that other options mention. Thus, the provided answer accurately captures the essence of what a karyotype represents in genetics.