What is the display of chromosome pairs arranged by size and shape called?

• A. Karyotype
• B. Sister chromatids
• C. Autosomes
• D. Phenotype

Answer: (A)

The display of chromosome pairs arranged by size and shape is called a karyotype. It’s created from a stained preparation of chromosomes, typically arrested in metaphase, and the chromosomes are ordered from largest to smallest with attention to the centromere position to reflect their shape. This visual arrangement, often shown as a karyogram, reveals the number and structure of an organism’s chromosomes and helps identify abnormalities like extra or missing chromosomes or rearrangements. Sister chromatids are the identical copies of a single chromosome held together at the centromere, not a whole set arranged by size. Autosomes are the non-sex chromosomes, a category of chromosomes included in a karyotype, but not the display method itself. Phenotype refers to the observable traits of an organism, not the chromosomal layout.