What part of the chromosome do genes lay on?

Nucleos is the cell part in that chromosomes are, nucleic acid is the general name given to dna and rna, centriole is a part of the cell that participates in the cell reproduction, im not sure but i think that is also the one that triggers the die of the cell. Of course the answer is spindle fibres, but to make this clear, DNA is a megamolecule formed by four nitrogenated basis adenine guanine tiamine and citosine, (AGCT) its suposed that those four letters codify any amino acid than forms the proteins inside any living being that has DNA (some only have RNA), now chromosomes are giant columns formed by the dna that is rolled over itself, so technically chromosomes are pure dna, and as I said, DNA codifies the aminoacids that forms protehines, this is they are the genes.