The genetic information will only be weitergeggeben by using enzymes but since these are outside the nucleus is located, the information must be read within ds nucleus (transcription) brought to the ribosomes, which in turn form the corresponding enzymes / proteins (translation).
DNS - RNS :
The RNA (ribonucleic acid) is the working copy of DNA. While the DNA base pairs adenine - thymine, guanine - contains cytosine, the RNA has no thymine. Speak with the RNA thymine is replaced by uracil: adenine - uracil, guanine - cytosine. Another difference is that the RNA masters only t stranded is. can share
replication (duplication of DNA)
Thus, a cell needs to double Dna the first (about afterwards again can share), a process known as replication.
Considering the cell cycle, replication happens in the S phase (see figure above).
The split happened in several locations at the DNA. When the DNA is threaded replication bubbles formed (structure of DNA in the reading of a gene or replication). work in these bubbles because nn two complexes against direction. This replication complex is composed of several elements: enzyme helicase (responsible for the "screwing" of the double helix), gyrase, proteins, Prina and various DNA polymerases (enzyme that is responsible for the production of the new DNA strand) is . The doubling happens in both directions, that is, until the two bubbles GATHERING (see illustration).
first Unwinding DNA and stabilizing the second Education is a koplementäre n DNA outside (3'-5 'direction) -> After the split formed new outer sides and there are therefore of a DNA strand two.
third Formation of Okazaki fragments and the binding to the DNA strand in entgegegengesetze direction.
-> After the split can be formed outside new pages (training runs in opposite directions) and there are therefore of a DNA strand two.
In prokaryotes, replication takes 40 minutes (about 4.7 x 10 6 base pairs)
In eukaryotes ( human chromosome ), This process would take several months. But through the "use" of replication bubbles it only lasts an hour. ( 150 x10 six base pairs )
read off by means of the enzyme transcriptase. It scans the string for the needed genetic information and separates the double strand in half by the end of the required information. On one of the now exposed strands of DNA are deposited at RNA nucleotides. If mRNA single carrier and single-stranded DNA into a "new" Double Stang have formed, dissolves from the mRNA strand and the DNA double-old Stang can connect again. By an NPC leaves the DNA copy of the nucleus, releasing it to the ribosomes.
Translation The resulting mRNA (messenger RNA) is then read by the ribosomes and converted to the corresponding proteins: The mRNA passes through the ribosome through. There, the mRNA, from the corresponding position is read and translated to the Arminosäurensequenz of the protein.
order needed and amino acids to obtain the so-called tRNA is formed. The tRNA is a smaller part of the RNA, which is shaped like a clover leaf. It has an amino acid binding site and a site for the anticodon (Komplimentäre bases corresponding to the mRNA).
The tRNA "sits" as on the mRNA and "obsolete" by the adjacent Arminosäure (a Arminosäure equivalent to 3 bases). In the next three bases, the next tRNA is the next appropriate Arminosäre. These acids form a chain. were joined after the Arminosäuren the tRNA detaches from the mRNA and the Arminosäure. If the operation is finished has been created from a finished Arminosäurekette protein that can be released into the plasma.
So have different constellations of Nukletide weider give the information. If the nucleotide pairs, it would connect to 16 different possibilities (4 ^ 2 = 16), that is enough for 20 amino acids.
why must therefore unite three Nukletide. 4^3=64. Da es nun "zu viele" Möglichkeiten gibt, heißt das also, dass es verschiedene Verbindungsmöglichkeiten gibt um ein und die selbe Aminosäure zu beschreiben.
Alle möglichen Basenkombinatioen können folgender Maßen dargestellt werden:
Diese Codesonne wird von innen nach außen gelesen.
Die Abkürzungen stehen für folgenden Aminosäuren:
Gly - Glycin
Phe - Phenylalanin
Leu - Leucin
Ser - Serin
Tyr - Tyrosin
Cys - Cystein
Trp - Tryptophan
Pro - Prolin
His - Histidin
GlN - Glutamin
Arg - Arginin
Ile - Isoleucine
Met - methionine
Thr - threonine
Asn - asparagine
Lys - lysine
Val - valine
Ala - Alanine
Asp - aspartic acid
Glu - glutamic acid
Gly - glycine
http://www.eduvinet .de/mallig/bio/Repetito/Bmgen3.html
http://www.zum.de/Faecher/Materialien/beck/bs11-71.htm
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