Question

What is the difference between chromatin fibre and chromosome ?

Answer 1

Chromatin fibre is unfolded, uncondensed, extended DNA. It is only visible when cell under goes division whereas chromosomes are condensed DNA and they are visible when the cell is divided.


hromatin chromosome Definition Structure Appearance Pairs Metabolic activity Presence Conformation Visualization

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.
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.
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.
Chromatin is unpaired.	Chromosome is paired.
Permissive to DNA replication, RNA synthesis (transcription) and recombination events.	Refractory to these processes.
Found throughout the cell cycle.	Distinctly visible during cell division (metaphase, anaphase) as highly condensed structures upto several thousand nm.
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.
Electron microscope (beads on string appearance)	Light microscope (classic four-arm structure when duplicated)