In the nucleus, the DNA double helix is packaged by special proteins (histones) to form a complex called chromatin. The chromatin undergoes further condensation to form the chromosome. So while the chromatin is a lower order of DNA organization, chromosomes are the higher order of DNA organization. An organism’s genetic content is counted in terms of the chromosome pairs present. e.g. humans have 23 pairs of chromosomes.
Comparison chart
 | Chromatin | Chromosome |
|---|---|---|
| Definition | In the nucleus, the DNA double helix is packaged by special proteins (histones) to form a complex called chromatin. The chromatin undergoes further condensation to form the chromosome. | A compact structure of nucleic acids and protein found in the nucleus of most living cells, carrying genetic information in the form of genes. |
| Structure | Composed of nucleosomes-a complex of DNA and proteins (called histones). Represent DNA folded on nucleoproteins by a magnitude of 50. The chromatin fiber is app. 10 nm in diameter. | Chromosomes are condensed Chromatin Fibers. They are a higher order of DNA organization, where DNA is condensed at least by 10,000 times onto itself. |
| Appearance | Chromatin Fibers are Long and thin. They are uncoiled structures found inside the nucleus. | Chromosomes are compact, thick and ribbon-like. These are coiled structures seen prominently during cell division. |
| Pairs | Chromatin is unpaired. | Chromosome is paired. |
| Metabolic activity | Permissive to DNA replication, RNA synthesis (transcription) and recombination events. | Refractory to these processes. |
| Presence | Found throughout the cell cycle. | Distinctly visible during cell division (metaphase, anaphase) as highly condensed structures upto several thousand nm. |
| Conformation | May have open (euchromatin) or compact (heterochromatin) conformations, which is dynamically regulated during the cell-cycle stages. | Predominantly heterochromatic state with a predetermined position in the nucleus and a specific shape such as metacentric, submetacentric, acrocentric, telocentric. |
| Visualization | Electron microscope (beads on string appearance) | Light microscope (classic four-arm structure when duplicated) |
Structure and Formation
The structural entity of chromatin is the nucleosome — a complex of DNA and histones. A chromatin fiber is approximately 10 nm in diameter. Chromatins represent DNA folded on nucleoproteins by a magnitude of 50.
Chromosomes are formed of compacted chromatin where DNA is condensed at least by 10,000 times onto itself.
Metabolic activity
While chromatin is permissive to DNA replication, RNA synthesis (transcription), and recombination events, the chromosomes are refractory to these processes as they are tightly coiled.
Presence
Chromatin is found in all stages of the cell cycle and they undergo further coiling to form chromosomes that are distinctly visible during cell division as highly condensed structures (upto several thousand nm). Depending on the number of chromosomes, a cell may be diploid or haploid.
Visualization
Chromatin is visible in a cell via an electron microscope where it shows the typical beads on string appearance.
Chromosomes are much easier to visualize and can be seen using a light microscope.
Conformation
Chromatin has either open (euchromatin) or compact (heterochromatin) conformations, which is dynamically regulated during the cell-cycle stages. Chromosomes have a predominantly heterochromatic state with a predetermined position in the nucleus and a specific shape such as metacentric, submetacentric, acrocentric or telocentric.
DNA 
Replication 
Mitosis 
Haploid 
Fraternal Twins 
Gamete
Comments: Chromatin vs Chromosome