Nucleosomes
When chromatin is tightly compacted and dense, it's called Heterochromatin. When chromatin is loosely packed, its called Euchromatin. Euchromatin is easily accessible to transcription enzymes, while herterochromatin makes transcription impossible because the enzymes cannot access the DNA. Therefore, a gene within heterochromatin cannot be expressed. Also, look up how histone modifications such as histone acetylation affect gene expression.
Hydrogen Bonds Adenine, Thymines, Guaines, and Cytosines.
Very simply put, a gene is a region of DNA that codes for a protein DNA is composed of 4 different nucleotide bases- guanine, adenine, thymine, and cytosine. A group of three of these is called a codon. A codon codes for a particular amino acid. A protein is composed of a chain of amino acids put together in the codons are in. Therefore the genetic information is the sequence of codons and by extension the sequence of nucleotide bases.
I suppose it's really just called DNA, but in some singe-celled organisms, it's just simply DNA. The DNA is found in the nucleus of a cell.
no its not!
nucleosomes
The section of DNA with eight associated histone proteins is called a nucleosome. Nucleosomes are the basic unit of DNA packaging in eukaryotic cells, where DNA is wrapped around a core of histone proteins to form a chromatin structure.
They're called histone proteins. There are 8histones proteins in which a loop of DNA wraps around twice. Then another histone protein called the H1 linker binds them together.
The protein around which chromosomal DNA is coiled is called histones. Histones help in organizing DNA into structural units called nucleosomes, which then further coil and condense to form chromatin fibers.
The enzyme responsible for unwinding DNA from around histone proteins is called DNA helicase. It catalyzes the separation of the two strands of the DNA double helix, allowing access for other enzymes and proteins to interact with the DNA.
Eukaryotic chromosomes consist of histone proteins and DNA. The histone proteins help to package and organize the DNA into a compact structure, called chromatin, which allows for efficient storage and regulation of genetic material.
Somewhat the difference between a brick and a brick wall. Chromosomes are made up of DNA molecules collected in units called genes ( leaving all else aside ) with attendant proteins, such as the histone proteins DNA wraps around.
Such a structure is called a Nucleosome
Chromatin is composed of DNA and histone proteins. Histone proteins help package and condense DNA into a complex structure that fits within the nucleus of a cell.
cell cycle
Purines, Pryimidine and Nucleotide are the subunits of DNA.
The complex of both histone and non-histone chromosomal proteins and DNA is known as chromatin.