What is a chromosome and what is its function?

• A. A protein that carries energy
• B. A lipid bilayer
• C. A structure containing DNA and proteins that carries genetic information and ensures its distribution during cell division
• D. A carbohydrate storehouse

Answer: (C)

Chromosomes are structures that package and protect the cell’s DNA, made from DNA wrapped around proteins called histones. Their job is to store genetic information in the form of genes and to ensure this information is faithfully transmitted when a cell divides. During division, chromosomes condense and align, and the sister chromatids are pulled apart by the spindle apparatus so each daughter cell receives an identical set of genetic instructions. This combination of carrying genes and enabling accurate distribution to daughter cells defines what a chromosome is. Other options describe different cellular components (energy-carrying molecules, the cell membrane, or energy storage molecules) and do not describe chromosomes.