The proteins in chromosomes perform structural functions and may be important for gene regulation. In any one species the chromosome number is constant, but the number of chromosomes varies from species to species. Organism Haploid Chromosome No. Some species only have 2 chromosomes. Remember this is the haploid number.
Most cells are diploid and have two copies of each chromosome.
See the electron microscope picture of human chromosomes. If you want to learn a lot more about how DNA is packaged in eukaryote chromosomes, go to the DNA Learning Center . The DNA is not contained within a special structure like the nucleus. The genome is typically contained in a single large DNA molecule and is not split up into many chromosomes. This DNA molecule is frequently a circle, rather than a long linear molecule found in eukaryote chromosomes.