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The power of the DNA molecule. Nucleic acids

Monomirnimi Lankans like є nucliatidi.

What's DNA?

All information about the budget and function of any living organism will take revenge on the genetic material coded by him. The basis of the genetic material to the organisms of the warehouse deoxyribonucleic acid (DNA).

DNA large organisms - the chain of dvolantsyuzhkov is a polymeric molecule. Last monomeric lanks (deoxyribonucleotide) in one її lantsyugu іdpovіdaє ( complementary) after deoxyribonucleotides in the first place. The principle of complementarity I will prevent the synthesis of new DNA molecules, identical to those of the other ones, with their subordinates ( replicas).

A dilenka of a DNA molecule, with a code sign, - gene.

Geni- a chain of individual genetic elements, which may have a strictly specific nucleotide sequence, which is the same as signs of an organism. Some codes are depleted, while others are deprived of the RNA molecule.

Information that can be found in genes, how to code bricks (structural genes), is deciphered through two last processes:

  • RNA synthesis (transcription): to synthesize DNA on the basis of the matrix messenger RNA (mRNA).
  • synthesis of bilka (translation): At the turn of the uzgodzhenoi robotics of the rich-component system for participation transport RNA (tRNA), mRNA, enzymes that other bile factors hello synthesis of a protein molecule.

All processes will ensure the correct transfer of encrypted DNA genetic information from nucleotides to amino acids. Amino acid after-life of a protein molecule the structure of that function.

Budova DNA

DNA- tse line organic polymer... Yogo - nucleotides, yaki, at my own house, store s:

At the same time, the phosphate group is assigned to 5'th in coal monosaccharide surplus, and organic base - up to 1'th.

There are two types of DNA present:


Budova nucleotides in DNA molecules

Have DNA monosaccharide representations 2'-deoxyribose, Show revenge only 1 hydroxyl group (OH) and in RNA - ribose, scho maє 2 hydroxyl groups (OH).

Nucleotides one by one phosphodiephiric links, at the same phosphate group 5'-carbon atom one nucleotide linked to Z'-OH-group deoxyribose medium nucleotide (baby 1). On one end of the polynucleotide lancet there is Z'-ON-group (Z'-kinets), and on іnshomu - 5'-phosphate group (5'-fin).

Equivalent DNA structure

Accepted vidіlyati 3 rіvnі DNA structures:

  • pervinnu;
  • secondarily;
  • tretinnu.

Primary DNA structure- the severity of the nucleotide rosetting in the polynucleotide lance of DNA.

Secondary DNA structure Stable between complementary pairs of bases and a sub-spiral of two antiparallel lanterns twisted to the right about one axis.

Spiraling coil 3.4nm, vіdstan mіzh lantsyuzhki 2nm.

Tretin structure of DNA - DNA supersperalization. The sub-spiral of DNA on some of the files can be added to the sub-spiral of the statements of the superspiral or of the open-ended ring form, but often because of the covalent ones of the past. The superspiral DNA structure will save the storage of the previous DNA molecule on the chromosomes. So, in the strong form of the genie, DNA molecules become 8 cm, and in the form of superspiral, it will settle in 5 nm.

Charghaf's rule

E. Chargaf's rule- the whole regularity of the nucleus instead of nitrogenous bases in DNA molecules:

  1. DNA molar parts purine and primidine bases of rivn: A +G = C+ T abo (A +G)/(C + T) = 1.
  2. DNA number of bases with aminogroups (A +C) one thing number of bases from ketogroups (G+ T):A +C= G+ T abo (A +C)/(G+ T) = 1
  3. The rule of equivalence, tobto: A = T, G = C; A / T = 1; G / C = 1.
  4. DNA nucleotide warehouse in organisms in different groups, specific and characterized specificity coefficient: (G + C) / (A + T). Have vishykh roslin and tvarin specificity coefficient less than 1, і amount slightly: від 0,54 before 0,98 , At microorganisms in more than 1

Watson-Krik DNA model

B 1953 James Watson that Francis Scream, based on the data of X-ray structural analysis of DNA crystals, went to visnovka, scho native DNA be stored in two polydimensional lanterns, which can be installed as a sub-spiral (Figure 3).

Naviti one on one polynucleotid lancers to be worn out at once watery clashes, scho establish themselves between the complementary bases of the prototypes of the lancers (Figure 3) adenine I'll set up a couple of tilki s timin, a guanin- s cytosine... A couple of basics AT stabilize two water ties and a couple G-C - trioma.

Dovzhin dvolantsyugovaya DNA depends on the number of pairs of complementary nucleotides ( P.n.). For DNA molecules that can be stored in thousands or millions of nucleotide pairs, taken as a single so onі m.p.n. for sure. For example, the DNA of chromosome 1 of humans is one subline of the helix 263 m.p.n.

Sugar phosphate molecule, which can be stored in phosphate groups of deoxyribose surpluses, 5'-3'-phosphodiephiric links, I will fix the "sidewalls of the gwent descent", and the bet of the basics ATі G-C- її gatherings (Figure 3).

Malunok 3: Watson-Krik DNA Model

Lantsyugi DNA molecule antiparallel: one of them is straight 3'→5', іnsha 5'→3'... As of the principle of complementarity even in one lance є nucleotide sequence 5-TAGGCAT-3 ′, then in a complementary lancet in the whole mission, the last 3′-ATCCGTA-5 ′... In tsyom vipadku Dvolantsyuzhkov's form viglyadatime in the following rank:

  • 5′-TAGGCAT-3 ′
  • 3-ATCCGTA-5 '.

Such a record 5'-end of the upper lance wait for the wrinkle, and 3'-fin- Right-handed.

Nose of genetic information can be satisfied with two main vimogs: vidtvoryuvatisya (replica) with high accuracyі Determinuvati (Koduvati) synthesis of protein molecules.

Watson-Krik DNA model More information about the cim vimogam, oskіlki:

  • Based on the principle of complementarity of the skin lancer, DNA can be used as a matrix for the adoption of a new complementary lanceug. Also, for one round, two daughter molecules are established, the skin is also nucleotide sequence, like the original DNA molecule.
  • the nucleotide sequence of the structural gene uniquely assigns the amino acid sequence of the protein coded by it.
  1. One DNA molecule for people in order 1.5 gigabytes of information... With a lot of DNA, all cells of human organisms take up 60 billion terabytes, which is stored on 150-160 grams of DNA.
  2. International DNA Day it is meant to be 25 April. Same day 1953 rock James watsonі Francis Creek published by the magazine Nature I will name my article "Molecular structure of nucleic acids" de described the sub-spiral of the DNA molecule.

List of literature: Molecular Biotechnology: Principle of Consumption, B. Glik, J. Pasternak, 2002

Life of DNA (deoxyribonucleic acids)

Viznachennya the understand "DNA"

Gene - the sequence of DNA segments, which can be used to zoom in on the approval of either an RNA molecule or a protein (Singer M., Berg P., 1998).

People have close to 30,000 geniv. In general, DNA has structural genes (that is, how to code bricks, how to go to induce structures to organism) take up 3-10% less.

Naymencha functional unit of DNA is composed of the following elements: structural gene, regulatory zones, regulatory genes.

Budova DNA molecule

DNA molecules can be seen in most sub-lants of polymers - polynucleotides, as monomers - nucleotides. Sliding lance of twists at the spiral. Tom's DNA is similar to gwint's go (look at the little ones in the gory). The dermal nucleotide includes one of the nitrogenous bases - adenine (A), guanin (G), cytosine (C) or thimin (T), one pentose molecule (p'iativcarbonate zucor) and one surplus of phosphoric acid. Name a DNA molecule and two complementary strands that create a sub-spiral. With a large amount of adenine of one thread, there is a pair of thymine (it stabilizes with two watery ligaments), and guanin is analogous to dressings with cytosine (three watery ligaments). The sequence of nitrogenous bases in DNA molecules does not contain the information required for the synthesis of proteins. DNA is a double molecule, which is composed of many nucleotides. For example, the human genome is composed of 46 chromosomes, which are based on DNA molecules, which in total are selected from about 3 billion nucleotide pairs.

In eukarotypes, the genetic material is located in the nucleus of the cell in the chromosomes. Chromosomes in the active stage show chromatin in the eyes. Chromatin avenge close to 40% of DNA, 40% of histones (low blood cells), approximately 20% of non-stone chromosomal cells and RNA trochas.

Video:Budova chromosome

DNA can be brought to "living systems", to "living molecules" on those days, and the smell is at the heart of life in the background, as well as a number of the most important powers of the living, spawn, health before reproduction. The DNA of the self-styled and self-sufficient, so that you can learn the pose of the clitine - in the viglyadi of the Viruses. The life of the DNA molecule passes through the life of the stage, so that we can imagine the life of folding biological systems - living organisms. Tse taki etapi yak populizhennya, dosrіvannya, robot (dіyalnіst) and "death".

Topic: Budova DNA

Home zavdannya

  1. Know and write the structural formulas of nucleotides: A, T, G, C, U.
  2. Knowledge of the structure of DNA molecules and their organization in chromosomes.
  3. Know the method of linking nucleotides in DNA vertically and horizontally. Understand about 3 "-5" calls.
  4. See the table with the genetic code to induce peptide molecules from the urahuvannya of the DNA box with a size of 12 or more nucleotides.

Video:Chromosomes, mitosis, replication

Etapi life DNA molecule

Population (replication) - dosage (chromosomes) - robot (transcription) - control (regulation) - species (mutation) - "death"

1. Replication of DNA - the popularization of a new daughter's DNA strand on the father's thread.
2. DNA dosage - chromosome formation.
3. Transcription of DNA - robotic DNA for matrix synthesis on RNA.
4. Regulation of transcription - control of DNA and transcription.
5. DNA repair - renewal of single-breasted girls.
6. The structure of DNA changes - mutations, transposons.
7. Degradation of DNA - ruinous during the skin cycle of replication.

1. Population - replication

Replication of DNA is more simple to pass, on the rakhunok "one, two, three", so in three stages: 1) initiation; 2) elongation; 3) term.

1.Inіtsіatsіya - fixing

Meta for launching a replica

Replication of a majestic DNA molecule is recited from a replica point. Qia point maє specific post-bagatu in pairs AT... Such uchkastki DNA yakraz і targets for bіlkіv, scho start replication. It is up to them to admit special bibliques, so that they can be informed that they will not be able to supply the replication enzymes. Helikaziі topoisomerase(Girazi) and in this order start the replication process. Helikaza splitting DNA into two lantsyugi. Establish a replica fork. The DNA molecule is rigidly fixed on the nuclear matrix and can be easily wrapped around when it is distributed. Tse blocking of heliakazi with lantsyug. Topoisomerase overcutting the DNA strand and recognizing the structural tension.
In one replicative villa there are two heliques, which collapse at other strands. The growth of lancers is fixed by DNA-binding beads. Forks shaped like replica forks are called “ori points” (origin - ear). At one time, eukarotiv set up a thousand of such vistas, which will preserve the high speed of the replica.

2. Elongatsia - continued (subdivided)

The growth of daughters of DNA on two of Batkiv's lantsyugs is not the same. DNA polymerase III prokaryotes and δ- or α-DNA polymerase eucarotes can help the synthesis of a new DNA lancet in a straight line 5 '> 3', because You can accept a new nucleotide only to the carbon in the 3 'position, but not in the 5' position.

Lantsyug with such a straightforward name lead ... The synthesis of a daughter strand of DNA is trivial without interruption. DNA-polymerase III abo-polymerase is continuously attached to its complementary nucleotide.

Lantsyug with polarity 3 '> 5' є vіdstayuchoї and get it in parts (also right next to 5 '> 3'). α-DNA-polymerase (or DNA-polymerase III) synthesizes on a whole lance of short dilyanka - fragments of Okazaki.

Synthesis of fragments of Okazaki and the leading lancer to reclaim from confirmation RNA primer (seeds ) up to 10-15 ribonucleotides with enzyme primazoy (RNA polymerase). It is not necessary for DNA polymerases to synthesize DNA from scratch, but rather dobudovuvatiіnuchiy lanceug. In parallel with the statements of the leading lancer or fragments of Okazaki, one can see ribonucleotides from the primers and replace them with DNA nucleotides. Replacement of ribonuclein dylyans (primers) for DNA dies is used for additional β-DNA polymerase, as it can exonuclease, so polymerase activity.

By such a rank, a replica is uncomfortable without a partial transcript.

The frequency of the replication (elongation) of DNA becomes close to 45000 nucleotides per quill, such a rank, the father's fork is distributed from the speed of 4500 rev / min. The price can be adjusted, for example, because the cooling fan is wrapped in a computer (1300-4800 rpm).

3. Termіnation - completion (end)

Completion of the replication will be seen once, if the glades between the Okazaki fragments are memorized by nucleotides (for the participation of DNA-ligase) from the statements of two permanent subordinate DNA lances, and if two replicas are detected. It is possible to see the twisting of the synthesized DNA from the statements of the superspirals.

The correctness of the replication will be ensured with the exact form of complementary pairs of bases and the number of DNA polymerases, which may include polymerase, other exonuclease activity and the development of the correct ways. When a non-complementary nucleotide is included, the enzyme knocks the croc back, causing it and going on with a polymerase reaction. To this, the replication process is leap-current.

For the completion of the replication, DNA methylation in the -GATS-dilenks is taken up by adenine (with N-methyladenine) and surplus cytosine with 5-methylcytosine. Methylation does not impair the complementarity of lancers and the need to form the structure of chromosomes and the regulation of transcription of genes.

In prokaryotes, such as bacteria, the DNA is replicable, not straightening in the linear molecule, so that it is lost in the characteristic for its cyclical form.

Video:P

2. Dosage - the formation of chromosomes and chromatin

3. Robot - transcription

Video:Blocking robotic gene

4. Management - regulation

5. Renovation (lagging) - reparation

6. Species - mutations .

7. "Death" - degradation during replication.

MOSCOW, 25 kvit - RIA Novini, Tetyana Pichugina. Exactly 65 years ago, the British scientists James Watson and Francis Creek published an article about deciphering the structure of DNA, laying the foundations of the new science - molecular biology. Tse vіdkrittya changed even more abundantly in the life of people. РІА Novini raspovіdaє about the power of the DNA molecule and about those for whom it is so important.

In the other half of the 19th century, biology was even more young science. All the time, they started until the end of the day, and the announcement about the decline, I hope it was already formed by Gregor Mendel, did not take a wide view.

In 1868, a young Swiss licar Fridrikh Misher arrived at the University of Tübingen (Nimechchin) to study scientific work. Win mav namir diznatisya, from which words the clitina is stored. For experiments with leukocyte vibra, it is easy to get hold of pus.

The resilient nucleus is made up of protoplasms, big and fat, Misher evolved with a great amount of phosphorus. Vin called the ciu molecule nuclein (“nucleus” latin - nucleus).

Tsya spoluka was acidic power, so the term "nucleic acid" is the name of the wine. The yogo prefix "deoxyribo" means that the molecule is to take revenge on the H-group and the tsukru. Z'yasuvalosya, but for the sake of it, I don't call it minions.

By the ear of the 20th century, we already knew that nucleus is a polymer (so that a molecule from lanoks can be repeated even more), lanes are folded with nitrogenous bases (adenine, thymine, guanine chromium and cytosomes), compact at the clitines, to share. I know how to convey the fallout signs by demonstrating the American geneticist Thomas Morgan at the drosophiles.

Model, yaka explained to geni

And the axis is able to destroy deoxyribonucleic acid at the nucleus of the cell, the DNA is quickened, and it is not too smart. I am aware of the structural role of chromosomes. The units of decay - genes - were attributed to the bilkovian nature. Having cut through the American glimpse of Oswald Everi, who has proved by a good way that the genetic material can be transferred from bacteria to bacteria for additional DNA.

It became clear that DNA required vivchati. Ale yak? At that hour, we will test the available x-rays. Schob enlightenment of biological molecules, which brought crystallization, ale smoothly. The deciphering of the structure of the bilky molecules by X-ray diffraction patterns was carried out at the Cavend laboratory (Cambridge, Great Britain). Young adolescents James Watson and Francis Creek, as they did it, were not a little bit of the most powerful experimental DNA tributes, the stink of the X-rays of the colleagues from the Royal College of Moris Uylkins and Rosalindi Franklin.

Watson and Creek proponated the model of the DNA structure, exactly as shown on the radiographs: two parallel lances are twisted in the right spiral. Leather lancers are stored with a large set of nitrogenous bases, strung on knots of candies and phosphates, and trimmed with water ties, stretched across the bases. Moreover, adenin is deprived of thymine, and guanin - of cytosine. This rule is called the principle of complementarity.

The Watson and Crick model explained some of the main functions of DNA: the replication of genetic material, its specificity, and the collection of information in the molecule and health of mutuvati.

We published their message in the journal Nature on April 25, 1953. Ten years later, Moris Uylkins was awarded the Nobel Prize for Biology (Rosalinda Franklin died in 1958 from cancer in 37 years).

"Now, it’s possible to state that the development of the DNA structure has played a role in the development of biology, as in physics - the appearance of the atomic nucleus. news, molecular biology ", - write Maksim Frank-Kamenetsky, a distinguished geneticist, DNA presenter, author of the book" Naigolovnisha Molecule ".

Genetic code

Now zalishalosya znatis, like a molecule din. Bulo see, how DNA revenge instructions for the synthesis of cells, such as the whole robot in the cells. Bilkies are a whole lot of polymers, which are stored in sets (after-signs) of amino acids, which are repeated. Moreover, amino acids - less than twenty. Looks like a creature is seen one in one set of bricks in the cells, so that by different messages of amino acids. The genetics of the stverdzhuval, which are given by genes, as they were respected, serve as a perceptive line of life. Ale scho is also a geni, though not for sure.

Clarity inside the author of the theory Great vibuhu Fizik Georgy Gamov, Fellow at the George Washington University (USA). Rumorize on the model of Watson's dvolancyuzhkovo spiral DNA and Scream, letting the gene go, so the gene is a DNA sequence, so that the sequence of lanes is the same - nucleotides. Oskilki dermal nucleotide is one of the chotir nitrogenous bases, then you just need to z'yasuvati, as chotiri elements code twenty. At the same time, I felt the idea of ​​the genetic code.

On the ear of the 1960s, it was established that proteins can be synthesized from amino acids in ribosomes - a kind of "factories" in the middle of a cell. Before starting to synthesize a protein, an enzyme comes close to the DNA, it releases a gene on the cob of a gene, synthesizes a copy of the gene in a small RNA (I call it matrix), then ribosomes for amino acids begin to wiggle the protein.

They also found out that the genetic code is trilterny. It means that one amino acid is three nucleotides. The unit of the code was called a codon. In ribosomes, information from mRNA is read codon by codon one last time. І cutaneous їх type of amino acids. Yak viglyadє cipher?

The power supply was made by Marshall Nirenberg and Henry Matthew from the USA. 1961 The rock stinks have improved their results at the biochemical congress near Moscow. Until 1967, the genetic code was deciphered. It appears to be universal for all cells of all organisms, but there are few distant inheritances for science.

Investigation of the structure of DNA and the genetic code has been reoriented to biologic predictions. Those who are skin-specific with a unique DNA sequence have radically changed criminalistics. Deciphering the human genome has given anthropologists a new method of evolving the evolution of our species. Not long ago, the DNA editor of CRISPR-Cas allowed him to forcefully push the gene engineering forward. Obviously, the majority of molecules have the greatest number of burning problems of people: cancer, genetic illnesses, old age.

Budova and DNA functions

Naming a parameter Value
Subject of the article: Budova and DNA functions
Category (thematic category) Osvita

DNA- Polymer, monomers such as є deoxyribonucleotide. The model of a spacious budovi DNA molecule as subordinate spirals was proponated to 1953 rock. J. Watson and F. Crick (robots M. Vilkins, R. Franklin, E. Chargaffa were victorious to inspire the stench model).

DNA molecule It is set up with two polynucleotid lancers, spirally twisting one beat of one at a time around the obvious axis, tobto. is a sub-spiral (vinyatok is a DNA virus-virus may be a single-lance DNA). The diameter of the subordinate spiral of DNA is 2 nm, the size between the suspension nucleotides is 0.34 nm, 10 nucleotide pairs per turn of the spiral. Dovzhina molecules can reach only a few centimeters. Molecular weight - tens and hundreds of millions. The total amount of DNA in the nucleus of human cells is close to 2 m. In eukarotic cells, DNA sets up a complex with cells that have a very specific spacious conformation.

Monomer DNA - nucleotide (deoxyribonucleotide)- to be stored from surplus of three rivers: 1) nitrogenous base, 2) p'entcarbon monosaccharide (pentozy) and 3) phosphoric acid. Nitrogen bases of nucleic acids are carried to the classes of primidin and purine. Pyrimidine DNA bases(may be at the warehouse of its own molecules in one circle) - timin, cytosine. Purine bases(may be two circles) - adenin and guanin.

Monosaccharide DNA nucleotide representations by deoxyribose.

Name the nucleotide є by the same type, name the basis. Nucleotides and nitrogenous bases are known by great letters.

The polynucleotide lancer takes root as a result of nucleotide condensation reactions. If there is a whole lot of 3 "-with carbon, an excess of deoxyribose of one nucleotide and an excess of phosphoric acid and of one phosphoether link(up to the category of mint covalent links). One end of a polynucleotide lancer will end with a 5 "lancet (it is called a 5" lancet), and one - 3 "lancet (3" lancet).

Against one lance of nucleotides, another lance of nucleotides grows. The growth of nucleotides in cich two lantsyugs is not of a type, but strictly meaningful: against adenine of one lancer in the first lancer, one grows time, and against guanine, it is cytosine, and adenine is a type of cytosine 'languages. The logic is that the nucleotides of the other DNA lances are strictly ordered to grow (adenin - thymine, guanin - cytosine) and vibrate one by one, the principle of complementarity... Slide means that J. Watson and F. Creek went to the understanding of the principle of complementarity in order to know the robots of E. Chargaff. E. Chargaff, having injected a great number of intelligence tissues and organs in different organisms, having inserted, in any fragment of DNA instead of surplus guanine, it was definitely in the place of cytosine, adenine - "Chargaff's rule"), but the explanation of the facts is not very helpful.

According to the principle of complementarity, the last of the nucleotides of one lancer is the beginning of the last of the nucleotides of the last one.

Lantsyugi DNA antiparallel (rizno-straightened), tobto. nucleotides of small lancers grow in opposite directions, and, also, 3 "- end of one lance is 5" - end of the last. The DNA molecule is indented from the gwent assemblies. "Railings" of cich descent - sugar-phosphate kistyak (excess deoxyribose and phosphoric acid will be left behind); "Steps" - complementary nitrogenous bases.

DNA function- Sberigannya and transmission of fallback information.

Budova and that function of DNA is the understanding of that kind. Classification and special features of the category "Budova and DNA functions" 2017, 2018.

You can get an idea of ​​the biological role of DNA in the whole statistics. Already, the abbreviation of all the knowledge of the great lavishness, but far from all the manifestation, but the trick. At the memory of the school course in biology, there is little knowledge of genetics and recession, and some of the foldable topic is given to children over and over. Ale ci znannya (the biological role of DNA, infused into the body) can be neuvorno cinnamon.

It’s more important, because nucleic acids are important functions, and it’s itself without interruption of life. Cy macromolecules are presented in two forms:

  • DNA (DNA);
  • RNA (RNA).

Smell є by transferring the genetic plan to that function of the cell's organism. Let's talk about them in a lecture.

DNA and RNA

Why, why not, like a science galuz to deal with such folding food, like:

  • vivchennya principіv zberіgannya;
  • її implementation;
  • broadcast;
  • vivchennya structure of biopolymers;
  • їх functions.

It is all about molecular biology. Itself in the whole hall of biological sciences one can know about nutrition about those, as the biological role of DNA and RNA.

Cytotolecular molecules, established from nucleotides, may be called "nucleic acids". It is here that information about organism is obtained, which is the reason for the development of the individual, the growth and decline.

Discovery of deoxyribonuclein and since 1868 Rik. Let us examine in the distance the development of the nuclei of the leukocytes and the spermatozoa of the moose. Further, the vyvchennya showed that DNA can be found in all cells of the roslin and creature nature. The Bula DNA model was presented in 1953 by the ROC, and the Nobel Prize for the screen was awarded in 1962 by the ROC.

DNA

How could it be that 3 types of macromolecules can be seen in all:

  • deoxyribonucleic acid;
  • ribonucleic acid;
  • bіlki.

The biological role of DNA is understood in my reports. Otzhe, the whole biopolymer conveyed the data about the drop, especially the development not only of the nose, but of the successive generations. - Nucleotide. Thus, DNA is the main component of chromosomes, to avenge the genetic code.

How old is the transfer of information? All on the right are polygons in the clever macromolecules self-create. The number of їх is indefinite, so it can be explained by great dimensions, and as inheritance - a majestic circle different sequence of nucleotides.

DNA structure

In order to understand the biological role of DNA in cells, it is necessary to understand the structure of this molecule.

Almost from the simplest, all nucleotides in their structures may have three components:

  • nitrogenous base;
  • pentose zukor;
  • phosphate group.

Dermal nucleotide nucleotide in DNA molecules revenge one nitrogenous base. There you can be absolutely be-yak from those who are young:

  • A (adenin);
  • G (guanin);
  • C (cytosine);
  • T (timin).

A і G - purini, and C, T and U (uracil) - pіramidini.

There are many rules for the management of nitrogenous bases, amended by the rules of Chargaff.

  1. A = T.
  2. R = Ts.
  3. (A + G = T + C) we can transfer all inconveniences and trimmings: (A + G) / (T + C) = 1 (the formula is the best for the hour when you review the data from biology).
  4. A + C = G + T.
  5. The value (A + C) / (H + T) is post_yna. For people, the average is 0.66, and from, for example, for bacteria - from 0.45 to 2.57.

Bud's skin DNA molecule is twisted by a spiral. Beastly respect for those who are polynucleotid lantsyugi є antiparallel. In order to expand the nucleotide pairs of one lancer, the last is less than the last. The skin turn of the chain spirals to replace 10 nucleotide pairs.

How can you skrіplyuyutsya around you? Why can't a molecule fall apart? All on the right side of the water link is between nitrogenous bases (between A and T - two, between G and C - three) and a hydrophobic interaction.

At the end of the process, I would like to guess that DNA is the largest organic molecules, which vary from 0.25 to 200 nm.

Complementarity

We make reports on the guys' calls. They also said to the one that the bet of nitrogenous people had to pretend not to be a chaotic character, but a suvorian afterthought. Thus, adenine can be associated with thymine, and guanine can be associated with cytosine. The last time the pairs of one lancet are roasted, the molecules are dictated by the rosetting of the first.

When replicating, or underpinning the establishment of a new DNA molecule, the whole rule, which I will call "complementarity", must be taken into account. You can note the onset of the regularity, as they guessed at the established rules of Chargaff - however, a number of advancing nucleotides: A і T, G і Ts.

Replication

Now let's talk about the biological role of DNA replication. It’s more than that, because the molecule is uniquely building up to self-development. By the term, the synthesis of a daughter molecule is reasonable.

In 1957, three models of the process are proponated:

  • it is conservative (it’s safe to see the molecule and pretend to be new);
  • it is napivconservative (cutting out a specific molecule on a mono-chain and attaching complementary bases to the skin of them);
  • dispersed (decay of the molecule, replication of fragments and sbir in the same order).

The replication process has three stages:

  • ініціяція (distribution of DNA dishes with an additional enzyme chelikase);
  • elongats_ya (podovzhennya lantsyuga by way of attracting nucleotides);
  • terminatsiya (reaching the necessary dozhini).

The whole folding process has a special function, so that the biological role is to ensure the exact transmission of genetic information.

RNA

If the role of DNA is biologically important, they now move forward to the examination (tobto RNA).

It’s more than enough that the molecule is not less important than DNA. Mi її can be found absolutely in any body, cells of prokaryotes and eukaritivs. Qia molecule is able to survive in certain viruses (see about RNA viruses).

The form of RNA is the appearance of a single lance of molecules, ale, as well as DNA, which is composed of some nitrogenous bases. In this case:

  • adenine (A);
  • uracil (U);
  • cytosine (C);
  • guanin (G).

All RNAs are subdivided into three groups:

  • matrix, yaku accepted nazivati ​​informatsionnoyu (speedy can be in two forms: iRNA chi mRNA);
  • ribosomal (rRNA).

Functions

Having chosen the biological role of DNA, as well as the peculiarities of RNA, we proponently move on to the special missions (functions) of ribonucleic acids.

Possibly from iRNA or mRNA, the main task of which is the transfer of information from the DNA molecule to the cytoplasm of the nucleus. Also mRNA is a template for bilka synthesis. Well, up to a high density change in the form of molecules, it is very low (close to 4%).

And the scent instead of rRNA in the cells of the road 80. The stench is necessary, the odds are the basis of ribosomes. Ribosomal RNA takes care of the fate of the synthesis of protein and folding of the polypeptide lancer.

The adapter, which vibrates lantsyug amino acids - tRNA, is used to transfer amino acids to the bottle synthesis bottle. Vidosotkovy vmіst in the clitine - about 15%.

Biological role

Pidib'єmo pidsumok: what is the biological role of DNA? At the moment of detection of the whole molecule, the obvious information from the drive could not be given, but at the same time, not all of the DNA and RNA were determined.

If we talk about the biological significance, then the role of the polarity in the transmission of decay information from generation to generation, the synthesis of white and blue structures.

It’s a lot of things that I’ve got into this version: the molecules are tied not only with the biological, but with the spiritual lives of living things. As soon as there are thoughts of metaphysics, then in the DNA there is a revenge of the past lives that divine energy.