DNA replication – 3D

DNA replication – 3D

DNA is a molecule made up of two strands twisted around each other in a double
helix shape. Each strand is made up a sequence of four chemical bases represented by the letters A, C, G and T. The two strands are complementary. This means that wherever there’s a T
in one strand there will be in an A in the opposite strand, and wherever there’s a C there will be a G in the other strand. Each strand has a 5′ end and a 3′ end. The two strands run in opposite
directions. This determines how each strand of DNA is replicated. The first step in DNA replication is to separate the two strands. This unzipping is done by an enzyme
called helicase and results in the formation of a
replication fork. The separated strands each provide a
template for creating a new strand of DNA. An enzyme called primase starts the
process. This enzyme makes a small piece of RNA called a primer. This marks the starting point for the
construction of the new strand of DNA. An enzyme called DNA polymerase binds to the primer and will make the new strand of DNA. DNA polymerase can only add DNA bases in one direction, from the 5′ end to the 3′ end. One of the new strands of DNA, the leading strand, is made continuously, the DNA polymerase adding bases one by one in the 5′ to 3′ direction. The other strand, the lagging strand,
cannot be made in this continuous way because it runs in the opposite
direction the DNA polymerase can therefore only
make this strand in a series of small chunks called Okazaki fragments. Each fragment is started with an RNA primer. DNA polymerase then adds a short row of
DNA bases in the 5′ to 3′ direction. The next primer is then added further
down the lagging strand. Another Okazaki fragment is then made and the process is repeated again. Once the new DNA has been made the enzyme exonuclease removes all
the RNA primers from both strands of DNA. Another DNA polymerase enzyme then fills in the gaps that are left behind with DNA. Finally the enzyme DNA ligase seals
up the fragments of DNA in both strands to form a continuous
double strand. DNA replication is described as semi-
conservative because each DNA molecule is made up
of one old, conserved strand of DNA and one new one.

David Anderson

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100 thoughts on “DNA replication – 3D

  1. Sangam Singh says:

    Understanding vedio

  2. Max Johnson says:

    Her voice and accent turned me on so much.

  3. Avik says:

    Very helpful
    Thanks a lot

  4. J'Artagnian Copria says:

    5 ahead of 3 = NAKED before SEX = leading strand

  5. vinodh i says:

    Please reply which is the template strand and which is the codind strand

  6. BeActive Behappy says:

    It is so amazing that this complex machinery of information (Here, DNA) replication has to take place without error that too at the rate of 2000 base pairs per second! Just imagine having to do it artificially on a system would be so expensive and time-consuming!

  7. yishen98 says:

    Thank you very much, really explained what my professor cannot

  8. Pubg Official says:


  9. Callie Vail says:

    Thank you. Made my reading easier.

  10. Selina Mnc says:

    Omg I love you so freackin much. German channels can‘t explain shit even though I watched 10000 Clips about DNA-Replication. So much love♥️♥️♥️😩😭

  11. Yobama says:

    I don't get the DNA ligase part how it seals the DNA I don't get it?!

  12. Ciel Alice says:

    This a great video keep up the good job 👍

  13. Nathalie Feijen says:

    Helped me so much! the only video i could find that explained it good enough for me to understand!



  15. Sandip Chand says:

    Thanks a alot…

  16. Abdi Gonzalez says:

    Valgo verga amigos

  17. I like Bread do you like Bread? Huh? says:

    Lot of stuff is missing in the video , The A proteins unbind the DNA double helix , The SSB prevent em from binding each other , replication bubble is formed thus . Them Helicase unwinds the DNA and topoisomerase helps in preventing torsional strain due to Helicase effect . 2 Replication Fork are formed , one on each side , Then comes the primase , forms the complex with Helicase called Primosome . Primase syn primmer ( short chain RNA molecula) , DNA polymerase starts Nacent Daughter strand syn on leading strand in 5-3 prime direction , the lagging strand DNA is syn in short fragments (Okazaki)
    After completion one Okazaki frag , primase is released and new primer is syn .. after completion of process primase is removed from DNA hybridase
    Gap removed after removal of prime is filled by nucleotides by complementary Basepaing I.e Okazaki acts as a fragment
    DNA ligase then seals the nicks req ATP
    Pray for my good grades my exam is on 16

  18. Pattharawarin kongpaiboon says:

    Today I have to test bout this one 😩😱

  19. Ayrsha Lipi says:

    it is very helpful for me…

  20. Heart Strings says:

    Nice video. Made me think how did people know this process.

  21. Sloppy joe says:

    Thank you!!! Could not understand. You made studying wayyy easier

  22. Mahnoor Ali marri says:

    Great job 👍🏻

  23. SAZID IMTIAZ says:


  24. Debabrata Laik says:

    Orientation of leading and lagging is wrong..
    3'-5' will be leading and lagging will be 5'-3'..Opposite is shown here in this video.

  25. Piyush Kumar says:

    it is very easy as well as interesting to learn the concepts by watching these videos..great job

  26. Anju negi says:

    From where primase came??

  27. Noxolo Mqadi says:

    Super helpful, thank you.

  28. Just Works Productions says:

    This doesn't actually explain why each protein moves, or where the proteins and RNA and DNA fragments actually come from.

  29. Sergey F. says:

    This is sooooo amazing with 3d visualisation I have chills when watching this… Gonna watch 9-10 times probably to remember it better…

  30. Uxie Xzxzxzx says:

    HELLO FAST GRADE 10 S.Y. 2019-2020 HAHAHA

  31. Estrella Swarez says:

    I’m French and I’ve understood it better in English because professors or unable to EXPLAIN IT CLEARLY IN A SIMPLE WAY !

  32. ANEATIONS says:

    Who is here because of Ms. Chien

  33. monkeynumber nine says:

    I am addicted to watching this.. it's so satisfying 😍

  34. Arshiya Farheen says:

    Helpful video 😊🌸

  35. Darshan Patel says:

    In the end in lagging strand primer is removed?

  36. Sarah Rivera says:

    thank you

  37. logang 4life says:

    Anyone here because their teacher is butthole

  38. logang 4life says:

    From the future of 2100 still explain better than my teacher

  39. Tech Buddy Creations says:

    Awesome presentation & effective use of graphics. Good work @yourgenome team👌 keep up the good work

  40. Vishakha Joshi says:

    Nice video 👍👍

  41. Ufak çaplı bir kriz {çevresiikipirehaş} says:

    Bizim okuldan biri varsa sa cndndm

  42. Berk Yılmaz says:

    FUNDAmantels 😀

  43. Mehjabeen shaikh says:

    The leading strand is continuous and the lagging strand is discontinuous . The okazaki fragments have gaps in between them. Please ensure that. The video was amazing!👍

  44. Kamal Kurre says:

    Great mam it wal to good

  45. Mahadev Sahu says:

    Please make in this video hindi

  46. It's the fox! says:

    But the primer is not DNA its RNA

  47. Galuh Kandyarucita says:

    wish me luck for the midtest

  48. Adya Singh says:


  49. Pescatarian Pantheist says:

    so dna polymerase only moves 5' to 3'? or is the daughter strand 5' to 3'?

  50. oh I thought I cared lol says:

    This is seriously the best video on YouTube about this topic 🌝❤

  51. Madhu Soni says:

    Very helpful

  52. Madhu Soni says:

    Oh god this is the first time 8 commented on youtube

  53. Evelyn Ramos says:

    como se descarga

  54. Veronica Shihepo says:

    Thank you so much

  55. Benedict S says:

    Amazing video. Simplifies a complex process. Well done!

  56. Armin Gamer says:

    It's stupid learning DNA replication without seeing the video

  57. Аиша Аиииша says:


  58. Abhishek Singh says:

    This is excellent way for study

  59. 김용호 says:

    I can simply understand this process thanks

  60. Sajesh Debbarma says:

    Best animated

  61. der Bayan says:

    Nice explanation 👍

  62. Umair Khattak says:

    Good job❤

  63. s.thiru thiru says:

    Thanks a lot

  64. Ritika Ghose says:

    SOOOOOOOOO COOL! So well explained, thank you!

  65. Udita Singh says:

    People comparing their teachers to a video like dude its animation…how do u expect a teacher to explaim a 3d model like tht on board. They tried their best

  66. Alvin Jan Austria says:

    5' – 3' is called a lagging strand

  67. Hashebul Hasan says:

    Thanks. from Bangladesh

  68. Elaine IU says:

    DNA replication
    -enzyme: helicase, primase, DNA polymerase, exonuclease, ligase

  69. Ahmed AlOtaibi says:

    I think that my biology teacher didn’t actually know how to explain this so he just resorted to this video lol

  70. Sabyl's Fine Jewelry says:

    This is a brilliant design. Any good computer engineer will agree. It’s also not the product of random chemical processes. First, it’s far too complex and elegant to be the result of random processes. And second, if it were, it would have a lot of useless steps and could easily be improved upon and optimized. We’re still just beginning to understand it. Cells are actually teaching us about microbiology. We would not have even thought of such beautiful and complex things.

    And in addition to the complexity of these designs, there’s the fact that functional proteins are extremely specific arrangements of amino acids. The probability of even one functional protein forming by random processes is 1 in 10^77. But when you consider that functional proteins are homochiral, meaning that only L-handed amino acids can used, the mystery of their existence becomes very great.

    And the simplest cells need something like 150 different functional proteins, each in sufficient quantities. And they all would have to come together at the same time and microscopic location. But even having them all doesn’t produce life. They have to be arranged properly to do anything useful, and then who knows what then makes them “alive”?

  71. Aneesa H. says:

    I wish this video mentioned when DNA polymerase I and III were being used. I believe III does the replication and I does strand checking/fragment removal?

  72. Melodi med says:

    thank you so much.you're perfect..😚

  73. oya's kitchen says:

    Perfect but i still didnt understand okazaki fragment part

  74. Motivasyon Motivasyon says:

    Altyaziyi ekleyen Allah senden razı olsun cok teşekkür ederim

  75. Harsh Kumbhat says:

    People take hours together to explain the same simple thing …….love this ……thank you so much

  76. Morgan Saje says:

    Easily the best replication video I've seen to date, thank you. I don't understand why it's so difficult for professors to explain this in a simple step by step process. I get that it's a complex topic, but damn, just go step by step. Stop talking about random enzymes in no discernible order.

  77. Kübra Nisa Ergün says:

    Where is the telomerase?

  78. Esedullah Yağlı says:

    Can u please tell me , in your country in what education level your are learning this thing ?

  79. Dounia S says:

    sooo helpful!!

  80. darkstyle - D2 - CSGO - OW says:

    holy shit thanks for this

  81. Laboun says:

    Thanks a lot

  82. Nj Rh says:

    Remember folks, your educators want you believe this all happened by chance. You're being lied to. God created all this.

  83. aya touati says:

    merci beaucop j'ai bien compris

  84. Sab Rango says:

    love it

  85. Jojokeksi O. says:

    Thank you so much. I'm not a native speaker and I still got it because it was so simple

  86. Khaloooda ١٢٣ says:

    Anyone from dar jana

  87. Parvez Hossain Adnan says:

    best and easy to understand

  88. Sophie B says:

    I am not even a native speaker but this was the best explanation I have even heard!

  89. Udayrockzz messi says:

    Thank you yourgenome. This was very helpful for me.You made it easier for me to understand.

  90. Dom Chocolate says:


  91. Ahmad Waheed says:

    Best explanation 😄😊

  92. Prathamesh Patil says:

    Thank you.

  93. max rex dinaco says:

    Pee pee poo poo

  94. Neela Pooja says:

    I am studying 10 th std it is very useful for me

  95. Aysha Khan says:

    I m really grateful

  96. taeland says:


  97. danh dang says:

    Who Onesome help me study English with . I from to Việt Nam.
    Now I study English very badly
    SOMEONE could help me

  98. amy liu says:

    who else is watching BTS crack while studying but is actually more of just watching BTS crack?
    Yes, I'm talking to you army, on a biology channel.


    There is no mention of topoisomerase enzyme action that causes unwinding

  100. Sara Reda says:

    رائع جداً

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