What is a genome?

• A. The location of a gene on a chromosome
• B. A single gene
• C. The complete set of genetic material of an organism
• D. The type of cell

Answer: (C)

A genome is the complete set of genetic material of an organism. It includes all the genes and the non-coding DNA in the nuclear chromosomes, plus any DNA in organelles such as mitochondria (and chloroplasts in plants). This is why it isn’t just one gene, nor a specific location on a chromosome, nor a cell type. The genome represents everything inherited that guides how the organism is built and functions, and sequencing a genome means mapping all of that hereditary material.