How are the following formed and involved in dna packaging in a nucleus of a cel
1)histone octomer
2) nucleosome
3)chromatin
4)differentiate between euchromatin and heterochromatin

When we analyze the structure of eukaryotic chromosome we find that it is composed of DNA and proteins. DNA is negatively charged and to stabilize the system some positively charged (basic) protein molecules are bound to it, These protein molecules are called histones.

There is large amount of DNA in our cells which creates a packaging problem. So, in order to maintain a high degree of organisation the DNA is folded. DNA helix combines with a group of eight histone molecules (histone octamer) to form structures called nucleosome.

Chromatin found in chromosomes consists of DNA and histone proteins. Chromatin can further be classified as euchromatin and heterochromatin.