Replication genetic information

DNA (deoxyribonucleic acid) (Section 28 7) A polynucleotide of 2 deoxynbose present in the nuclei of cells that serves to store and replicate genetic information Genes are DNA... 

An answer to this apparent riddle is provided by RNA. Ribonucleic acid is actually a DNA equivalent, since it can store and replicate genetic information. Importantly, it is also a protein equivalent, since it can catalyze critical chemical reactions. Indeed, the first life-forms were probably entirely RNA based, and RNA has remained part of our cellular systems (Watson, 2004). Thus, RNA translates the genetic information coded for in our DNA into information that proteins can understand and act upon and does so in a remarkable manner. 

Once the broad outlines of DNA replication and protein biosynthesis were established, scientists speculated about how these outlines affected various "origins of life" scenarios. A key question concerned the fact that proteins are required for the synthesis of DNA, yet the synthesis of these proteins is coded for by DNA. Which came first, DNA or proteins How could DNA store genetic information if there were no enzymes to catalyze the polymerization of its nucleotide components How could there be proteins if there were no DNA to code for them ... 

Nucleus The nucleus is separated from the cytosol by a double membrane, the nuclear envelope. The DNA is complexed with basic proteins (histones) to form chromatin fibers, the material from which chromosomes are made. A distinct RNA-rich region, the nucleolus, is the site of ribosome assembly. The nucleus is the repository of genetic information encoded in DNA and organized into chromosomes. During mitosis, the chromosomes are replicated and transmitted to the daughter cells. The genetic information of DNA is transcribed into RNA in the nucleus and passes into the cytosol where it is translated into protein by ribosomes. 

DNA replication yields two DNA molecules identical to die original one, ensuring transmission of genetic information to daughter cells widi exceptional fidelity. 

Extrachromosomal autonomously replicating circular closed DNA molecules encoding non-essential supplementary genetic information, like antibiotic resistance or metabolic capacities. 

The characteristics of a covalent bond between two atoms are due mainly to the properties of the atoms themselves and vary only a little with the identities of the other atoms present in a molecule. Consequently, we can predict some characteristics of a bond with reasonable certainty once we know the identities of the two bonded atoms. For instance, the length of the bond and its strength are approximately the same regardless of the molecule in which it is found. Thus, to understand the properties of a large molecule, such as how DNA replicates in our cells and transmits genetic information, we can study the character of C=0 and N- H bonds in much simpler compounds, such as formaldehyde, H2C=0, and ammonia, NH,. 

The amplification of genetic information, i.e., the replication of parent DNA molecules, is achieved by means of an entire set of enzymes. The major players are a DNA-gyrase for unwinding of the double helix, proteins to separate the two antiparallel DNA strands at the replicational junction, single-stranded binding proteins (SSB) that prevent the... 

All biological organisms have the ability to reproduce themselves. The instructions for self-replication are stored and transmitted by macromolecules called nucleic acids. There are two types of nucleic acids, one that stores genetic information and one that transmits the information. Genetic information is stored in molecules of deoxyribonucleic... 

In the nuclei of all eukaryotic cells, DNA is tightly wrapped around an octamer of histone proteins and is compacted into a dense structure known as chromatin. In order to access the genetic information which is required in numerous essential cellular processes including DNA replication, gene expression and DNA repair, chromatin needs to be partially unwound. One important mechanism to regulate chromatin structure and thus to control the access of the genomic DNA is through histone modifications [1-6]. The histone octamer is composed of two copies of H2A, H2B, H3 and H4 core histone proteins. Their tails, that protrude out of the surface of the... 

The nucleus contains bundles of a fibrous material known as chromatin, which is made up of mixed proteins and deoxyribonucleic acid (DNA), the substance that carries the genetic information of the living organism of which the cell is a component. All cells replicate by division. When a cell replicates, DNA in the chromatin of the nucleus passes the genetic information from one generation to the next one. As the cell divides, the chromatin clusters into rodlike structures known as chromo-... 

Cycle 2 the matrix replication cycle. The matrix molecule can multiply by polymerisation in the presence of a component from cycle 1 it contains all the genetic information required by the whole system. 

A plasmid is an autonomous, covalently closed circular (or linear) double-stranded and self-replicating DNA molecule found in most bacterial species and in some eukaryotes. Although the genetic information contained in a plasmid concerns replication, stability and autonomous transferability, their actual replication relies on the replication apparatus of the host cell. 

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