The hereditary information of an organism is contained within its DNA (deoxyribonucleic acid). DNA is a complex molecule that carries the genetic instructions for building and maintaining an organism.

Here's a breakdown:

* Genes: Specific segments of DNA that code for particular traits, like eye color or hair texture.

* Chromosomes: Long strands of DNA that are organized into structures within the nucleus of a cell. Humans have 23 pairs of chromosomes, for a total of 46.

* Nucleus: The control center of a cell, where chromosomes reside.

So, the hereditary information is essentially stored within the genes located on the chromosomes found inside the nucleus of a cell.