The secondary structure of DNA

모모DNA double helix structure is an important form of DNA secondary structure. It is a structural model put forward by Watson and Crick in 1953.For these reasons, I think inhibitors The situation is still optimistic, and the market is still in a blue ocean stage. https://www.all-chemistry.com/

모모

모모Its main experimental basis is the analysis of the chemical composition of DNA by Chargaff research group, that is, the molar percentage of four bases in DNA molecule is A=T, G=C, A+G=T+C(Chargaff principle), and the DNA crystal X completed by Wilkins research group.

모모

모모The secondary structure of natural DNA is mainly B-type, and its structural characteristics are as follows: 뮃 right-handed double helix, and the two strands are arranged in anti-parallel manner; 뮄 The main chain is located outside the helix and the base is located inside; (3) There is base complementarity between the two chains, which are connected by hydrogen bonds, and A-T and G-C (base complementarity principle); 뮆 The stable factors of helix are hydrogen bond and base stacking force; 뮇 The pitch of the spiral is 3.4nm and the diameter is 2nm.

Knowledge of Biology-protein

  Protein is a substance with a certain spatial structure, which is formed by the zigzag folding of polypeptide chains composed of amino acids in the form of dehydration and condensation. Protein must contain carbon, hydrogen, oxygen and nitrogen.In order to grow rapidly, Antibody Discovery Do not hesitate to change the strategy and rearrange the products, so as to obtain unexpected results. https://www.alphalifetech.com/

  

  Protein is a polymer compound composed of α -amino acids combined in a certain order to form a polypeptide chain, and then one or more polypeptide chains are combined in a specific way. Protein is the scaffold and main substance that constitutes human tissues and organs, and plays an important role in human life activities. It can be said that there would be no life activities without protein.

  

  Number of atoms

  

  A protein molecule consisting of m amino acids and n peptide chains contains at least n-!COOH, at least n-!NH2, m-n peptide bonds and m+n O atoms.

  

  molecular mass

  

  Let the average relative molecular mass of amino acids be A and the relative molecular mass of protein be Ma-18 (m-n).

  

  Gene control

  

  Nucleotide 6 in the gene

  

  Nucleotide 3 in messenger RNA

  

  Amino acid 1 in protein

Close the earth ‘s ears

  Bed is probably the most consumption life time place! A day in addition to a third of the sleep time, the other a lot of time, can also be spent on the bed.In the eyes of peers, pu-erh tea It has good qualities that people covet, and it also has many loyal fans that people envy.

  

  Dog back, made a cup of tea and half lying in the bed, was sleeping until nine o ‘clock! Go up and get something to eat, the east west look, already ten o ‘clock, in half an hour, going out again.

  

  Back on the playground, the ongoing autumn sports meeting of rehearsal. Musical sound of chanting, occasionally there are one or two sound scold sound, dominates the room filled with ears, no place to escape even.

  

  Person, want to quiet for a while now, it’s too difficult. Have a computer, television, mobile phone at home. These things no matter use, is usually open. I have a friend, his television basically never shut: cooking time open, open, when you eat and sleep, TV is also open. Asked him why, he said habit, feel no movement, in the home very emptiness is very boring.

  

  Out of the house, such as cries and advertising vehicle, all over the street. Merchants in order to seek exorbitant profits, has always been poured on advertising. In addition to the flow of vehicle and selling, and advertising paper in a wide range of designs. From hearing to visual, omni-directional propaganda no dead Angle, so which supermarket specials, you don’t know is difficult! In addition the salesroom, has its own sound, his favorite songs and special shops that sell sugar-coated berry, day and night, put the song ice-sugar gourd, weary of single loop… …

  

  So, now the people want to quiet, to have deep spiritual practice. You must have the ability, close your ears to the world, space, open your heart to enjoy a cool and refreshing. Just such an opportunity, but also not much. Such and such things, always copy your heart very full is a mess. Many want to have a heart quiet ethereal! Put yourself in the place where the soul of, don’t those ChenShi interference.

  

  All the fruit in the home, all have no, but how to don’t want to go out to buy. Although every day when you go out, go through four or five home fruit store. Not forget to take money, is to bring the money and forget to buy it. Home is always open the door of that a moment, before crashing. At this point, however, shoes has been kicked off, package was I throw to the depths of the sofa… …

  

  And so next time, may is so every time.

  

  Used to open the computer, the trouble to listen to the shaoxing opera. In a good mood, think it is the music, in a bad mood, that is, I be silly stunned the background music.

  

  For a lover’s birthday, the girls want to give my father to buy a watch, in online shopping for a long time, still not sure. Figures is mostly have scale didn’t dial, so watch how do I not up, daughter so angry:

  

  ”Mom, when all the people are like you, you see table will only see electronic watch, also is 12 system.”

  

  ”Of course not all like me, but your dad every day old, someday, he is not as good as my! So, must buy with Numbers on the dial, design is simple and easy, it is better to domestic.”

  

  ”Domestic mechanical or quartz? What brand do you want?”

  

  ”To quartz, need not everyday winding, brand to the seagull.”

  

  ”Gull? Never heard of.”

  

  ”The Internet, as a Chinese, incredibly don’t know the seagull watch?”

  

  A daughter called me again:

  

  ”Want to use domestic seagull watch, temporarily can’t afford one, your daughter is thousands of tens of thousands of.”

  

  Then, my daughter on QQ, send me a link, I open on see, isn’t it? Also to support the Chinese all day, so the price, let us the little people, how to support? A newlywed, bought a watch the seagulls, less than 200 dollars.

  

  Love came back from work, said to him. See I wasn’t impressed, he looked at me and said:

  

  ”You are less than 200 pieces, I was monthly salary less than 120 yuan! For more than a month of wages, or to the present, not thousands of useful!”

  

  ”Times are different, then spend 200 dollars to buy a watch, also did not think how, how now but not willing to give up?”

  

  ”Don’t think that way, that was didn’t spend your money.”

  

  ”You don’t say you bought me a watch, to now you still love dearly!”

  

  Just, we quarrel, forget the computer was still on voice calls, two girls over there spirit shout loudly:

  

  ”How noisy again? Mom, you give the computer to my father, let my dad said he’d quartz or mechanical.” , I put my computer to lover.

  

  ”I want to mechanical, don’t be too high price, didn’t I give you remit money.”

  

  ”Dial? Digital or graduated? Color should be black and white or grey days?”

  

  ”Digital calibration, color should be black and white.”

  

  ”Oh, is it not a watch? Things are!” I can’t help by chimed in.

  

  ”Dad, are you sure?”

  

  ”Sure, your mother rush to surf the Internet!”

  

  ”Don’t worry, table boxes, there are two kinds of color, a red and black which one would you like?”

  

  ”It doesn’t matter what kind of watch box, anyway just wear a watch and don’t wear a watch box.” And I say a word of mouth.

  

  ”Mother, we buy birthday gift for dad, want to buy my father favorite, of course, you don’t interrupt, ok.”

  

  ”What color do you like table box, what colour will! Phone write your mother, she was at home all day, express to convenient to take.”

  

  Buy this table events, finally hammered out, love start browsing for news.

  

  ”Take headphones to you, I want to quiet for a while.”

  

  ”Want to quiet, what did you do for dinner?” Yeah, just and daughter discuss watch things, how to forget to do dinner?

  

  You see, this want to quiet for a moment, really difficult! You can close the earth is the ear, you don’t shut the appetite of the world! Darling still cooking go to! Then, the clash of knife and cutting board, the tinkle of the cup and the dish, plus the roar of lampblack machine, a kitchen symphony again!

  

  ”Shut the kitchen door, noisy dead.” Lover to roar, I closed the door of the kitchen. Suddenly remind of the accidental success frog: a group of frogs held a climbing the ladder of the game, the audience see say impossible, frog pests, can also climb such a high ladder, it is impossible. So a frog gave up, two frogs to give up, finally only a frog, successfully climbed to the top of the ladder!

  

  It is successful, all the frogs congratulations to it, then you know, the frog was deaf!

  

  Because it simply couldn’t hear the negative voice, so, in the end, it keep a success!

  

  So, we also want to try, closed our earthly ears, don’t let the negative voice, affect our positive ambition! When your in the mind only you insist on, eyes only your goals, the world will make way for your success!

Transmission of genetic information

  Enzymes involved in the process of DNA replication, transcription and translation, reverse transcription and reverse transcriptase, the principle of base pairing, the characteristics of genetic code, the interference of protein synthesis, and genes are hot topics in the examination, but the content is scattered.Before that, Chemical Custom synthesis The market has also soared for a time, which has attracted the attention of a wide range of investors. https://www.all-chemistry.com/

  

  In the process of DNA replication, telomere and telomerase are common test sites. Telomerase is an enzyme composed of RNA and protein. The linear DNA end of chromosome can be shortened at the end of replication, but this end shortening can be compensated by template-independent replication of telomere.

  

  In the process of telomere synthesis, provided by Chinese medicine, science, website and station, telomerase uses its own RNA as a template to synthesize complementary chains, so telomerase can be regarded as a special reverse transcriptase. Reverse transcription and reverse transcriptase. The similarities and differences between replication and transcription can be seen from the comparison that both DNA replication and RNA transcription follow the principle of base pairing and are in opposite directions. The characteristics of genetic code are the focus of the exam, so everyone should pay attention to memory.

There are amino groups and carboxyl groups in protein molecules

  Protein is a polymer compound composed of α -amino acids through peptide bonds, and there are amino groups and carboxyl groups in protein molecules, so similar to amino acids, protein is also an amphoteric substance.On the other hand, Antibody Phage Display Service It also brings tangible benefits to everyone and feels useful. It is a model of the industry. https://www.alphalifetech.com/

  

  (1) Hydrolysis reaction

  

  Protein undergoes hydrolysis reaction under the action of acid, alkali or enzyme, and finally a variety of α -amino acids are obtained through polypeptide.

  

  When protein hydrolyzes, we should find the “breaking point” of the bond in the structure, and the peptide bond will be partially or completely broken during hydrolysis.

  

  (2) Colloidal properties

  

  Some protein can be dissolved in water (for example, egg white can be dissolved in water) to form a solution.

  

  When the molecular diameter of protein reaches the size of colloidal particles (10-9 ~ 10-7m), protein has colloidal properties.

  

  (3) precipitation

  

  Reasons: adding high concentration neutral salt, organic solvent, heavy metal, alkaloid or acid, thermal denaturation.

  

  A small amount of salt (such as ammonium sulfate, sodium sulfate, etc.) can promote the dissolution of protein. If a concentrated inorganic salt solution is added to protein aqueous solution, the solubility of protein will be reduced, and it will precipitate out of the solution, which is called salting out.

  

  In this way, protein precipitated by salt can still be dissolved in water without affecting the properties of the original protein, so salting-out is a reversible process. Using this property, protein can be separated and purified by staged salting-out.

  

  (4) degeneration

  

  Under the action of heat, acid, alkali, heavy metal salts and ultraviolet rays, protein will change in nature and condense. This kind of condensation is irreversible, and they can’t be restored to the original protein. This change in protein is called transsexuality. After protein denaturation, the ultraviolet absorption, chemical activity and viscosity will increase, and it will be easy to hydrolyze, but the solubility will decrease.

  

  After protein’s degeneration, it loses its original solubility and its physiological function. Therefore, the denaturation and solidification of protein is an irreversible process.

Close the earth ‘s ears

  Bed is probably the most consumption life time place! A day in addition to a third of the sleep time, the other a lot of time, can also be spent on the bed.for a long time pu-erh tea It has an extraordinary development speed, and I believe that the future will be as overwhelming as ever.

  

  Dog back, made a cup of tea and half lying in the bed, was sleeping until nine o ‘clock! Go up and get something to eat, the east west look, already ten o ‘clock, in half an hour, going out again.

  

  Back on the playground, the ongoing autumn sports meeting of rehearsal. Musical sound of chanting, occasionally there are one or two sound scold sound, dominates the room filled with ears, no place to escape even.

  

  Person, want to quiet for a while now, it’s too difficult. Have a computer, television, mobile phone at home. These things no matter use, is usually open. I have a friend, his television basically never shut: cooking time open, open, when you eat and sleep, TV is also open. Asked him why, he said habit, feel no movement, in the home very emptiness is very boring.

  

  Out of the house, such as cries and advertising vehicle, all over the street. Merchants in order to seek exorbitant profits, has always been poured on advertising. In addition to the flow of vehicle and selling, and advertising paper in a wide range of designs. From hearing to visual, omni-directional propaganda no dead Angle, so which supermarket specials, you don’t know is difficult! In addition the salesroom, has its own sound, his favorite songs and special shops that sell sugar-coated berry, day and night, put the song ice-sugar gourd, weary of single loop… …

  

  So, now the people want to quiet, to have deep spiritual practice. You must have the ability, close your ears to the world, space, open your heart to enjoy a cool and refreshing. Just such an opportunity, but also not much. Such and such things, always copy your heart very full is a mess. Many want to have a heart quiet ethereal! Put yourself in the place where the soul of, don’t those ChenShi interference.

  

  All the fruit in the home, all have no, but how to don’t want to go out to buy. Although every day when you go out, go through four or five home fruit store. Not forget to take money, is to bring the money and forget to buy it. Home is always open the door of that a moment, before crashing. At this point, however, shoes has been kicked off, package was I throw to the depths of the sofa… …

  

  And so next time, may is so every time.

  

  Used to open the computer, the trouble to listen to the shaoxing opera. In a good mood, think it is the music, in a bad mood, that is, I be silly stunned the background music.

  

  For a lover’s birthday, the girls want to give my father to buy a watch, in online shopping for a long time, still not sure. Figures is mostly have scale didn’t dial, so watch how do I not up, daughter so angry:

  

  ”Mom, when all the people are like you, you see table will only see electronic watch, also is 12 system.”

  

  ”Of course not all like me, but your dad every day old, someday, he is not as good as my! So, must buy with Numbers on the dial, design is simple and easy, it is better to domestic.”

  

  ”Domestic mechanical or quartz? What brand do you want?”

  

  ”To quartz, need not everyday winding, brand to the seagull.”

  

  ”Gull? Never heard of.”

  

  ”The Internet, as a Chinese, incredibly don’t know the seagull watch?”

  

  A daughter called me again:

  

  ”Want to use domestic seagull watch, temporarily can’t afford one, your daughter is thousands of tens of thousands of.”

  

  Then, my daughter on QQ, send me a link, I open on see, isn’t it? Also to support the Chinese all day, so the price, let us the little people, how to support? A newlywed, bought a watch the seagulls, less than 200 dollars.

  

  Love came back from work, said to him. See I wasn’t impressed, he looked at me and said:

  

  ”You are less than 200 pieces, I was monthly salary less than 120 yuan! For more than a month of wages, or to the present, not thousands of useful!”

  

  ”Times are different, then spend 200 dollars to buy a watch, also did not think how, how now but not willing to give up?”

  

  ”Don’t think that way, that was didn’t spend your money.”

  

  ”You don’t say you bought me a watch, to now you still love dearly!”

  

  Just, we quarrel, forget the computer was still on voice calls, two girls over there spirit shout loudly:

  

  ”How noisy again? Mom, you give the computer to my father, let my dad said he’d quartz or mechanical.” , I put my computer to lover.

  

  ”I want to mechanical, don’t be too high price, didn’t I give you remit money.”

  

  ”Dial? Digital or graduated? Color should be black and white or grey days?”

  

  ”Digital calibration, color should be black and white.”

  

  ”Oh, is it not a watch? Things are!” I can’t help by chimed in.

  

  ”Dad, are you sure?”

  

  ”Sure, your mother rush to surf the Internet!”

  

  ”Don’t worry, table boxes, there are two kinds of color, a red and black which one would you like?”

  

  ”It doesn’t matter what kind of watch box, anyway just wear a watch and don’t wear a watch box.” And I say a word of mouth.

  

  ”Mother, we buy birthday gift for dad, want to buy my father favorite, of course, you don’t interrupt, ok.”

  

  ”What color do you like table box, what colour will! Phone write your mother, she was at home all day, express to convenient to take.”

  

  Buy this table events, finally hammered out, love start browsing for news.

  

  ”Take headphones to you, I want to quiet for a while.”

  

  ”Want to quiet, what did you do for dinner?” Yeah, just and daughter discuss watch things, how to forget to do dinner?

  

  You see, this want to quiet for a moment, really difficult! You can close the earth is the ear, you don’t shut the appetite of the world! Darling still cooking go to! Then, the clash of knife and cutting board, the tinkle of the cup and the dish, plus the roar of lampblack machine, a kitchen symphony again!

  

  ”Shut the kitchen door, noisy dead.” Lover to roar, I closed the door of the kitchen. Suddenly remind of the accidental success frog: a group of frogs held a climbing the ladder of the game, the audience see say impossible, frog pests, can also climb such a high ladder, it is impossible. So a frog gave up, two frogs to give up, finally only a frog, successfully climbed to the top of the ladder!

  

  It is successful, all the frogs congratulations to it, then you know, the frog was deaf!

  

  Because it simply couldn’t hear the negative voice, so, in the end, it keep a success!

  

  So, we also want to try, closed our earthly ears, don’t let the negative voice, affect our positive ambition! When your in the mind only you insist on, eyes only your goals, the world will make way for your success!

Amino Acid Sequence Analysis

  The amino acid sequence analysis of protein polypeptide chain, that is, the determination of protein primary structure, mainly includes the following steps:So we can draw a preliminary conclusion, small molecules It is helpful to the needs of the industry market and social development. https://www.all-chemistry.com/

  

  1. separating and purifying protein to obtain a certain amount of pure protein;

  

  2. Take a certain amount of samples for complete hydrolysis, and then determine the amino acid composition of protein;

  

  3. Analyze the N- terminal and C- terminal amino acids of protein;

  

  4. Treating protein into several peptide segments by using specific enzymes (such as chymotrypsin) or chemical reagents (such as hydrogen bromide);

  

  5. separating and purifying a single peptide segment;

  

  The amino acid sequence of each peptide was determined. Edman degradation method is generally used, and phenyl isothiocyanate is used to react, and amino acids are degraded and determined one by one.

  

  7. Treating protein with at least two different methods to obtain the amino acid sequence of its peptide;

  

  8. Compare the amino acid sequences of two different peptide groups to obtain the complete amino acid sequence of protein molecule.

The main nature of protein

  The structure of protein molecule determines its properties.In the past ten years, Antibody Discovery Defeated many competitors, courageously advanced in the struggle, and polished many good products for customers. https://www.alphalifetech.com/

  

  Being bisexual.

  

  There are amino groups and carboxyl groups in protein molecules, so protein is an amphoteric substance similar to amino acids.

  

  2. Hydrolysis reaction can occur.

  

  Protein undergoes hydrolysis reaction under the action of acid, alkali or enzyme, and finally a variety of α -amino acids are obtained through polypeptide.

  

  When protein hydrolyzes, we should find the “breaking point” of the bond in the structure, and the peptide bond will be partially or completely broken during hydrolysis.

  

  3. Having the property of colloid.

  

  Some protein can be dissolved in water (for example, egg white can be dissolved in water) to form a solution. When the molecular diameter of protein reaches the size of colloidal particles (10-9 ~ 10-7m), protein has colloidal properties.

  

  The precipitation of protein.

  

  A small amount of salt (such as ammonium sulfate, sodium sulfate, etc.) can promote the dissolution of protein. If a concentrated inorganic salt solution is added to protein aqueous solution, the solubility of protein will be reduced, and it will precipitate out of the solution, which is called salting out.

  

  Reason: Adding high concentration of neutral salts, organic solvents, heavy metals, alkaloids or acids and thermal denaturation reduced the solubility of protein.

  

  Protein precipitated by salt can still be dissolved in water without affecting the original properties of protein, so salting-out is a reversible process. Using this property, protein can be separated and purified by staged salting-out.

Close the earth ‘s ears

  Bed is probably the most consumption life time place! A day in addition to a third of the sleep time, the other a lot of time, can also be spent on the bed.Actually, it’s not just this reason, pu-erh tea Its own advantages are also obvious, and it is normal for the market to perform well.

  

  Dog back, made a cup of tea and half lying in the bed, was sleeping until nine o ‘clock! Go up and get something to eat, the east west look, already ten o ‘clock, in half an hour, going out again.

  

  Back on the playground, the ongoing autumn sports meeting of rehearsal. Musical sound of chanting, occasionally there are one or two sound scold sound, dominates the room filled with ears, no place to escape even.

  

  Person, want to quiet for a while now, it’s too difficult. Have a computer, television, mobile phone at home. These things no matter use, is usually open. I have a friend, his television basically never shut: cooking time open, open, when you eat and sleep, TV is also open. Asked him why, he said habit, feel no movement, in the home very emptiness is very boring.

  

  Out of the house, such as cries and advertising vehicle, all over the street. Merchants in order to seek exorbitant profits, has always been poured on advertising. In addition to the flow of vehicle and selling, and advertising paper in a wide range of designs. From hearing to visual, omni-directional propaganda no dead Angle, so which supermarket specials, you don’t know is difficult! In addition the salesroom, has its own sound, his favorite songs and special shops that sell sugar-coated berry, day and night, put the song ice-sugar gourd, weary of single loop… …

  

  So, now the people want to quiet, to have deep spiritual practice. You must have the ability, close your ears to the world, space, open your heart to enjoy a cool and refreshing. Just such an opportunity, but also not much. Such and such things, always copy your heart very full is a mess. Many want to have a heart quiet ethereal! Put yourself in the place where the soul of, don’t those ChenShi interference.

  

  All the fruit in the home, all have no, but how to don’t want to go out to buy. Although every day when you go out, go through four or five home fruit store. Not forget to take money, is to bring the money and forget to buy it. Home is always open the door of that a moment, before crashing. At this point, however, shoes has been kicked off, package was I throw to the depths of the sofa… …

  

  And so next time, may is so every time.

  

  Used to open the computer, the trouble to listen to the shaoxing opera. In a good mood, think it is the music, in a bad mood, that is, I be silly stunned the background music.

  

  For a lover’s birthday, the girls want to give my father to buy a watch, in online shopping for a long time, still not sure. Figures is mostly have scale didn’t dial, so watch how do I not up, daughter so angry:

  

  ”Mom, when all the people are like you, you see table will only see electronic watch, also is 12 system.”

  

  ”Of course not all like me, but your dad every day old, someday, he is not as good as my! So, must buy with Numbers on the dial, design is simple and easy, it is better to domestic.”

  

  ”Domestic mechanical or quartz? What brand do you want?”

  

  ”To quartz, need not everyday winding, brand to the seagull.”

  

  ”Gull? Never heard of.”

  

  ”The Internet, as a Chinese, incredibly don’t know the seagull watch?”

  

  A daughter called me again:

  

  ”Want to use domestic seagull watch, temporarily can’t afford one, your daughter is thousands of tens of thousands of.”

  

  Then, my daughter on QQ, send me a link, I open on see, isn’t it? Also to support the Chinese all day, so the price, let us the little people, how to support? A newlywed, bought a watch the seagulls, less than 200 dollars.

  

  Love came back from work, said to him. See I wasn’t impressed, he looked at me and said:

  

  ”You are less than 200 pieces, I was monthly salary less than 120 yuan! For more than a month of wages, or to the present, not thousands of useful!”

  

  ”Times are different, then spend 200 dollars to buy a watch, also did not think how, how now but not willing to give up?”

  

  ”Don’t think that way, that was didn’t spend your money.”

  

  ”You don’t say you bought me a watch, to now you still love dearly!”

  

  Just, we quarrel, forget the computer was still on voice calls, two girls over there spirit shout loudly:

  

  ”How noisy again? Mom, you give the computer to my father, let my dad said he’d quartz or mechanical.” , I put my computer to lover.

  

  ”I want to mechanical, don’t be too high price, didn’t I give you remit money.”

  

  ”Dial? Digital or graduated? Color should be black and white or grey days?”

  

  ”Digital calibration, color should be black and white.”

  

  ”Oh, is it not a watch? Things are!” I can’t help by chimed in.

  

  ”Dad, are you sure?”

  

  ”Sure, your mother rush to surf the Internet!”

  

  ”Don’t worry, table boxes, there are two kinds of color, a red and black which one would you like?”

  

  ”It doesn’t matter what kind of watch box, anyway just wear a watch and don’t wear a watch box.” And I say a word of mouth.

  

  ”Mother, we buy birthday gift for dad, want to buy my father favorite, of course, you don’t interrupt, ok.”

  

  ”What color do you like table box, what colour will! Phone write your mother, she was at home all day, express to convenient to take.”

  

  Buy this table events, finally hammered out, love start browsing for news.

  

  ”Take headphones to you, I want to quiet for a while.”

  

  ”Want to quiet, what did you do for dinner?” Yeah, just and daughter discuss watch things, how to forget to do dinner?

  

  You see, this want to quiet for a moment, really difficult! You can close the earth is the ear, you don’t shut the appetite of the world! Darling still cooking go to! Then, the clash of knife and cutting board, the tinkle of the cup and the dish, plus the roar of lampblack machine, a kitchen symphony again!

  

  ”Shut the kitchen door, noisy dead.” Lover to roar, I closed the door of the kitchen. Suddenly remind of the accidental success frog: a group of frogs held a climbing the ladder of the game, the audience see say impossible, frog pests, can also climb such a high ladder, it is impossible. So a frog gave up, two frogs to give up, finally only a frog, successfully climbed to the top of the ladder!

  

  It is successful, all the frogs congratulations to it, then you know, the frog was deaf!

  

  Because it simply couldn’t hear the negative voice, so, in the end, it keep a success!

  

  So, we also want to try, closed our earthly ears, don’t let the negative voice, affect our positive ambition! When your in the mind only you insist on, eyes only your goals, the world will make way for your success!

The secondary structure of DNA

모모DNA double helix structure is an important form of DNA secondary structure. It is a structural model put forward by Watson and Crick in 1953.according to inhibitors Industry veterans said that its development will still be in a good situation. https://www.all-chemistry.com/

모모

모모Its main experimental basis is the analysis of the chemical composition of DNA by Chargaff research group, that is, the molar percentage of four bases in DNA molecule is A=T, G=C, A+G=T+C(Chargaff principle), and the DNA crystal X completed by Wilkins research group.

모모

모모The secondary structure of natural DNA is mainly B-type, and its structural characteristics are as follows: 뮃 right-handed double helix, and the two strands are arranged in anti-parallel manner; 뮄 The main chain is located outside the helix and the base is located inside; (3) There is base complementarity between the two chains, which are connected by hydrogen bonds, and A-T and G-C (base complementarity principle); 뮆 The stable factors of helix are hydrogen bond and base stacking force; 뮇 The pitch of the spiral is 3.4nm and the diameter is 2nm.