Which term describes the count and appearance of chromosomes in a cell?

• A. Karyotype
• B. Epistasis
• C. Pleiotropy
• D. Polygenic inheritance

Answer: (A)

The main idea here is how scientists describe the structure and number of chromosomes in a cell. The term that captures that is karyotype. A karyotype is the organized visualization of all the chromosomes in a cell, showing how many chromosomes are present and what their physical features are—size, shape, and banding patterns. It’s typically prepared from dividing cells, stained, and arranged in a standard order from largest to smallest, with the sex chromosomes included. This profile is used to spot chromosomal abnormalities, such as an extra chromosome or a missing chromosome. Epistasis refers to interactions between genes where one gene’s effect depends on another gene; pleiotropy is when one gene influences multiple traits; polygenic inheritance is when a trait is controlled by many genes.