Search results
Results from the WOW.Com Content Network
Chromatin is a complex of DNA and protein found in eukaryotic cells. [1] The primary function is to package long DNA molecules into more compact, denser structures. This prevents the strands from becoming tangled and also plays important roles in reinforcing the DNA during cell division , preventing DNA damage , and regulating gene expression ...
In contrast to most eukaryotic cells, mature sperm cells largely use protamines to package their genomic DNA, most likely to achieve an even higher packaging ratio. [17] Histone equivalents and a simplified chromatin structure have also been found in Archaea, [18] suggesting that eukaryotes are not the only organisms that use nucleosomes.
Eukaryotic chromosomes are also stored in the cell nucleus, while chromosomes of prokaryotic cells are not stored in a nucleus. Eukaryotic chromosomes require a higher level of packaging to condense the DNA molecules into the cell nucleus because of the larger amount of DNA. This level of packaging includes the wrapping of DNA around proteins ...
These proteins tend to be highly conserved across a majority of eukaryotic species. [13] [14] In mammals, key architectural proteins include: Histones: DNA is wrapped around histones to form nucleosomes, which are basic units of chromatin structure. Each nucleosome consists of 8 histone protein subunits, around which roughly 147 DNA base pairs ...
Organization of DNA in a eukaryotic cell. Each eukaryotic chromosome consists of a long linear DNA molecule associated with proteins, forming a compact complex of proteins and DNA called chromatin. Chromatin contains the vast majority of the DNA in an organism, but a small amount inherited maternally can be found in the mitochondria.
During the cell division, chromatin compaction increases even more to form chromosomes, which can cope with large mechanical forces dragging them into each of the two daughter cells. [1] Many aspects of transcription are controlled by chemical modification on the histone proteins, known as the histone code .
Think of the cell wall as a wicker basket in which a balloon has been inflated so that it exerts pressure from the inside. Such a basket is very rigid and resistant to mechanical damage. Thus does the prokaryote cell (and eukaryotic cell that possesses a cell wall) gain strength from a flexible plasma membrane pressing against a rigid cell wall ...
In eukaryotic organisms, the DNA of each cell is organized into separated chromosomes, which are composed of chromatin, a mixture of DNA and many different groups of proteins. Among them, the structural proteins (that are not histones ) bind the chromatin fiber around themselves forming a long, continuous axis or backbone that gives the ...