- During the process of cell division, chromatin undergoes significant structural changes to ensure the accurate distribution of genetic material to daughter cells.
- In the interphase of the cell cycle, DNA exists as loosely packed chromatin, allowing for gene expression and replication.
- However, as the cell prepares to divide during mitosis or meiosis, chromatin condenses and coils tightly to form distinct structures called chromosomes.

- These chromosomes are highly organized complexes of DNA and proteins, which facilitate the proper segregation of genetic material. Each chromosome consists of two identical sister chromatids joined at a centromere, but the entire condensed structure is collectively referred to as a chromosome during cell division.

- Nucleosomes are the fundamental units of chromatin, consisting of DNA wrapped around histone proteins, but they themselves do not represent the higher-order structure visible during division.
- Chromatids refer to the duplicated halves of a chromosome, not the entire structure.
- Centrioles are organelles involved in spindle formation, not a form of chromatin.

Reference: Molecular Biology of the Cell, 6th Edition, Chapter 16 - The Cell Cycle