Karyotypes can be studied to determine an organism’s chromosomal makeup and to detect genetic defects. down syndrome is a genetic disorder that is also called trisomy 21. what would trisomy 21 look like in a karyotype?

Trisomy 21 would show presence of an extra copy of chromosome 21 in a karyotype

Explanation:

Humans are diploid organisms, having 23 pairs of chromosomes (46 chromosomes in each cell. Trisomy represents a chromosomal disorder, with presence of an additional chromosome (total 47 chromosomes, instead of 46).  

Down syndrome is a genetic disorder caused by trisomy of chromosome 21. Karyotype is used to represent appearance and number of chromosomes present in nucleus of a cell.

Thus, in karyotype trisomy 21 there would be an additional copy of chromosome 21. Diagram of karyotype trisomy 21 is attached with answer.

A karyotype is the number and appearance of chromosomes in the nucleus of an eukaryotic cell.