● In `color{Violet}"eukaryotes"`, this organisation is much more `color{Violet}"complex"`.
● There is a set of `color{Violet}"positively charged"`, `color{Violet}"basic proteins"` called `color{Violet}"histones"`.
● A protein `color{Violet}"acquires charge"` depending upon the abundance of `color{Violet}"amino acids"` residues with `color{Violet}"charged side chains"`.
● Histones are rich in the basic amino acid residues `color{Violet}"lysines and arginines"`.
● Both the amino acid residues carry `color{Violet}"positive charges"` in their side chains.
● Histones are organised to form a `color{Violet}"unit of eight"` molecules called as `color{Violet}"histone octamer"`.
● The negatively charged `color{Violet}"DNA"` is `color{Violet}"wrapped"` around the positively charged `color{Violet}"histone octamer"` to form a structure called `color{Violet}"nucleosome"`.
● A typical nucleosome contains 200 bp of DNA helix.
● Nucleosomes constitute the `color{Violet}"repeating unit"` of a structure in nucleus called `color{Violet}"chromatin"`, thread-like stained (`color{Violet}"coloured"`) bodies seen in nucleus.
● The nucleosomes in chromatin are seen as `color{Violet}"beads-on-string"` structure when viewed under `color{Violet}"electron microscope"` (EM) .
● The beads-on-string structure in chromatin is `color{Violet}"packaged"` to form `color{Violet}"chromatin fibers"` that are further coiled and condensed at `color{Violet}"metaphase stage"` of cell division to form `color{Violet}"chromosomes"`.
● The packaging of chromatin at `color{Violet}"higher level"` requires additional set of proteins that collectively are referred to as `color{Violet}"Non-histone Chromosomal"` (`color{Violet}"NHC"`) `color{Violet}"proteins"`.
● In a typical nucleus, some region of chromatin are `color{Violet}"loosely packed"` (and stains `color{Violet}"light"`) and are referred to as `color{Violet}"euchromatin"`.
● The chromatin that is more `color{Violet}"densely packed"` and stains `color{Violet}"dark"` are called as `color{Violet}"Heterochromatin"`.
● Euchromatin is said to be `color{Violet}"transcriptionally active chromatin"`, whereas heterochromatin is `color{Violet}"inactive"`.
● In `color{Violet}"eukaryotes"`, this organisation is much more `color{Violet}"complex"`.
● There is a set of `color{Violet}"positively charged"`, `color{Violet}"basic proteins"` called `color{Violet}"histones"`.
● A protein `color{Violet}"acquires charge"` depending upon the abundance of `color{Violet}"amino acids"` residues with `color{Violet}"charged side chains"`.
● Histones are rich in the basic amino acid residues `color{Violet}"lysines and arginines"`.
● Both the amino acid residues carry `color{Violet}"positive charges"` in their side chains.
● Histones are organised to form a `color{Violet}"unit of eight"` molecules called as `color{Violet}"histone octamer"`.
● The negatively charged `color{Violet}"DNA"` is `color{Violet}"wrapped"` around the positively charged `color{Violet}"histone octamer"` to form a structure called `color{Violet}"nucleosome"`.
● A typical nucleosome contains 200 bp of DNA helix.
● Nucleosomes constitute the `color{Violet}"repeating unit"` of a structure in nucleus called `color{Violet}"chromatin"`, thread-like stained (`color{Violet}"coloured"`) bodies seen in nucleus.
● The nucleosomes in chromatin are seen as `color{Violet}"beads-on-string"` structure when viewed under `color{Violet}"electron microscope"` (EM) .
● The beads-on-string structure in chromatin is `color{Violet}"packaged"` to form `color{Violet}"chromatin fibers"` that are further coiled and condensed at `color{Violet}"metaphase stage"` of cell division to form `color{Violet}"chromosomes"`.
● The packaging of chromatin at `color{Violet}"higher level"` requires additional set of proteins that collectively are referred to as `color{Violet}"Non-histone Chromosomal"` (`color{Violet}"NHC"`) `color{Violet}"proteins"`.
● In a typical nucleus, some region of chromatin are `color{Violet}"loosely packed"` (and stains `color{Violet}"light"`) and are referred to as `color{Violet}"euchromatin"`.
● The chromatin that is more `color{Violet}"densely packed"` and stains `color{Violet}"dark"` are called as `color{Violet}"Heterochromatin"`.
● Euchromatin is said to be `color{Violet}"transcriptionally active chromatin"`, whereas heterochromatin is `color{Violet}"inactive"`.