What structure in the cell is made of DNA and associated proteins where genes are located?

The correct answer is a chromosome. Chromosomes are structured forms of DNA that are tightly coiled and associated with proteins called histones. This organization allows the genetic material, which includes genes, to be packed into a compact form suitable for cell division and function. Each chromosome contains many genes, which are specific sequences of DNA that code for proteins or define traits.

In contrast, a gene refers specifically to a segment of DNA that contains the instructions for making a particular protein but does not encompass the broader structural features of chromosomes. The nucleus is the organelle that houses chromosomes and serves as the control center for the cell, but it is not the structure itself where genes are located. Ribosomes, on the other hand, are not made of DNA; they are the sites of protein synthesis in the cell and work with mRNA to translate genetic information into proteins. This distinction highlights the unique role of chromosomes in storing and organizing genetic information.