can someone explain what chromatin, the stuff in the nucleus does?in words a middle schooler would understand!

Answer 1

chromatin is made of DNA and proteins.
You have probably heard of DNA. It carries all the information needed to make every cell in your body. it is a long long strand of chemical that carries a code. It gets copied once into a new strand of DNA each time the cell divides to make a new cell. Also parts of the code get 'read' and translated into all the new proteins that do the work of the cell. The proteins in the body are the building blocks and also control the chemical reactions.
By the way, the proteins in the chromatin organize all the DNA and control which proteins are made when.

Answer 2

the DNA in our cells is not in a free, elongated form. rather it's intricately wound around proteins that help to compact it into a smaller form. proteins called histones are the major proteins involved in this. they form little disc-like structures. the DNA wraps around each disc almost two times (like a small spool) one after another. One histone disc plus the two turns of the DNA around it is called a 'nucleosome'

if you look at DNA and histones by electron microscopy, you would see what looks like beads on a string. the beads are the histones and the string is the DNA.

http://chemistry.umeche.maine.edu/CHY431/Beads.jpg

There are some other proteins (besides histones) that also help to package the DNA into a more compact form. they are not the primary players, but they do have a role.

together, the DNA plus the histones, plus the accessory proteins are referred to as 'chromatin'. chromatin is the natural state of our DNA in our cells. without it the DNA would take up too much space and be a tangled mess.

One last point, there are several layers of compaction as shown in this picture, with the DNA around the histone disc being the first layer.

http://upload.wikimedia.org/wikipedia/en/4/4b/Chromatin_Structures.png

Answer 3

Chromatin is a mixture of DNA and specific proteins found in the nuclei of cells. Each of your cells has about 7 feet of DNA in it. That DNA has to be folded and compacted so it fits in the nucleus. There are a bunch of different proteins that bind to DNA and help compact it. Other proteins in chromatin are involved in telling a cell which genes to use and which not to use.