Viruses (Updated)

  • Published on May 22, 2018
  • Explore the lytic and lysogenic viral replication cycles with the Amoeba Sisters! This video also discusses virus structures and why a host is critical for viral reproduction. Expand details for table of contents and further reading suggestions! This updated video replaces our older virus video from 2013.
    Table of Contents:
    0:29 Intro to a Virus
    1:10 Virus Structure
    2:30 Lytic Cycle
    3:41 Lysogenic Cycle
    4:48 HIV
    5:52 Viruses in Gene Therapy, Pesticide
    We cover the basics in biology concepts at the secondary level. If you are looking to discover more about biology and go into depth beyond these basics, our recommended reference is the FREE, peer reviewed, open source OpenStax biology textbook:
    Further Reading Suggestions:
    Learn more about the Nuclear Polyhedrosis Virus (NPV)- a virus that can target pest insects.
    How does Gene Therapy Work? (from NIH)
    We received a great comment asking about how viral DNA may go undetected. Check out this great journal article:
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    The Amoeba Sisters videos demystify science with humor and relevance. The videos center on Pinky's certification and experience in teaching biology at the high school level. For more information about The Amoeba Sisters, visit:
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Comments • 344

  • Amoeba Sisters
    Amoeba Sisters  Year ago +49

    This topic is now an Unlectured Series topic! One of the question starters in the Unlectured topic mentions two therapies still being explored that can use viruses: *phage therapy* and *gene therapy.* Something fascinating to research if you have an interest in learning more about viruses.

    • Isabella Gomez
      Isabella Gomez 3 months ago +1

      Love this thank u.❤️

    • Do you know da wae
      Do you know da wae 11 months ago

      @Mr. Potato Im the potato

    • Mr. Potato
      Mr. Potato Year ago +1


    • JustACrisp
      JustACrisp Year ago +1

      your the best teacher on youtube i mean that i hope you ser my message you've helped me so much

    • Valhalla Arts
      Valhalla Arts Year ago +2

      Amoeba Sisters, I have been a sufferer of what people call "cystic acne" since I was around the age of 15 and I have tried a lot of things to cure or at least put it in a state of idle and I have found nothing that works so far. I'm curious if instead of this "cystic acne" issue myself and others have is not a bacterial problem but a viral problem and that is the reason that antibiotics do not work for us. Any thoughts or questions or anything you may have to help will be greatly appreciated.

  • Spencer Workman
    Spencer Workman 9 hours ago

    RIP KOBE. I Love you

  • I have Crippling depression

    *dies cutely

  • Hey It's Me GNWND
    Hey It's Me GNWND 21 hour ago

    23 years old me is more entertained by this kind of video than me in 16-18 years old. Idk why I’m here.

  • vaibhav agarwal
    vaibhav agarwal Day ago

    I love viruses. Lol!!!

  • life 7
    life 7 Day ago

    Are viral pestisides considered organic pestisides

  • Angie M
    Angie M 2 days ago

    Watch out for the wuhan virus in china, its a 3.9 danger level its killed 40 and 800 infected. Way it kills, amoanuia. Symptoms cold fever coughing also airborn. Way of travel, airports, can stay in one area for weeks started in china. Please be careful we have a few chases in America already

    ALEXIA KLM 2 days ago

    and that's on corona virus

  • Sreya Roy
    Sreya Roy 3 days ago

    I love your drawings they are so cute

  • Hmpz SZN
    Hmpz SZN 3 days ago

    Whos hear after hearing about the conviurs

  • Mehdi Aya
    Mehdi Aya 9 days ago

    Thank you ❤️
    Your drawings are so helpful

  • Rewel
    Rewel 11 days ago

    I was just listening to Eminem, forgot that I switched to this video and thought for half a minute it was a skit / interlude or something from the album xD

  • Terra Asara
    Terra Asara 13 days ago +1

    Bacteria: I will end every form of life
    Bacteriophage: excuse me?

  • Xeodile
    Xeodile 13 days ago +1

    the amoeba sisters have been drafted 😥

  • alireza sha'bani
    alireza sha'bani 13 days ago +1


  • Acrappy Crap
    Acrappy Crap 15 days ago +1

    4:44 This was quite informative and interesting. Love this stuff

  • jahaan Patel
    jahaan Patel 15 days ago

    what the 3 list of illnesses caused by viruses

    • Xeodile
      Xeodile 13 days ago

      jahaan Patel cold, flu, polio

  • MuShroom Me
    MuShroom Me 19 days ago +6

    I am entering the sea of comments, and this particular comment Will most likely go forever unseen.

  • kla 1 subscriber
    kla 1 subscriber 20 days ago

    I thought it was a computer virus Lol

  • Patrick playing!
    Patrick playing! 22 days ago


  • Andreia Moreira
    Andreia Moreira 28 days ago

    Quem tem que morrer não é o Jesús, são vocês. Vocês são ocos por dentro.

  • ADiLA Nageeb
    ADiLA Nageeb 29 days ago +1

    lol I haven't stopped watching these videos even after I graduated..
    Ameoba sisters videos are simply attractive and entertaining in a very cute way

  • Alexandros Retsinas

    You didn't explain how the virus is getting stopped from killing the person

  • Aggl Yusr
    Aggl Yusr Month ago +2

    amazing as always ! Thank you

  • Anesh kumar
    Anesh kumar Month ago +5

    Imagine going subatomic like ant man and getting trapped in virus realm

    • Artix Vektör
      Artix Vektör 16 hours ago

      that makes me think of bacteriophage as mosquitoes to bacterias LOL

  • Mint Man
    Mint Man Month ago

    dont hate the videos but i HAD to get it to 200 dislikes

    IKKUP P Month ago

    Cool name amoeba sister🤣🤣😍😍😅😅

  • regor testado
    regor testado Month ago

    Virus the cellphone to cheat the ml for lulu box

  • Carlos Canales
    Carlos Canales Month ago

    Hello this are good and bad videos

  • Blue Fesler
    Blue Fesler Month ago +1

    My teacher loves the amoeba sisters. So basically for homework we just summarize all their videos!⛑⚛

  • Hamda A.Bushager
    Hamda A.Bushager Month ago

    I am a medical student and your videos are so helpful. Thank you so much!

  • Rowe Lilienthal
    Rowe Lilienthal Month ago

    bruh my teacher is forcing me to watch this👺👺👺👺

  • imago
    imago 2 months ago

    Am i the only one who didn't come here for some exam but out of pure interest..?

  • Gcse guru
    Gcse guru 2 months ago


  • Twitch Cobraaa
    Twitch Cobraaa 2 months ago +1


  • Aya Aya
    Aya Aya 2 months ago

    The animation is great!

  • BubbleChubs _
    BubbleChubs _ 2 months ago

    Anyone here from FCPS biology?

  • BubbleChubs _
    BubbleChubs _ 2 months ago

    Is my laptop alive then?

    Wait.... Oh Jesus...

  • Chloe Inez
    Chloe Inez 2 months ago

    I’m depressed bc I have a test in biology tomorrow and I have no clue what’s going on.

  • Shafe
    Shafe 2 months ago

    well, I used to hate viruses...

  • Nathan
    Nathan 2 months ago

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    Are you Deceived By Church/Man's Sinful Ways, Vain Theologies, Sciences, Politics, Entertainment, etc?
    False/Demonic Religions, Evolution/Atheism, rapture, easy believe gospel, one modern pastor, pagan holidays (Christmas-Easter, etc) ritual gatherings, worldliness (movies, sports, entertainment, pet idolatry, etc), unbiblical dress, uncovered women's heads, instrumental music, worship pastors, youth pastors, building centered faith, no Matthew 18 discipline, the tithe, heretical not be deceived!
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    3) Born again... you must be born of God's spirit to ever see eternal life. In this new life, He gives you a new heart and mind to then serve Him. (John 3:3, John 3)
    4 ) Holiness with obedience.... if your changed by God you WILL, as fruit, strive to leave all sin, worldliness, carnality and false ways (like man made religion) and obey His commands and be holy in all your ways. (1 Peter 1:15 / Hebrews 5:9 / Hebrews 12:14)
    5) Endure in your faith.... You MUST keep clinging to Christ via this saving faith to the end of your life, lest you fall away and have believed in vain. (Matthew 24:13, Matthew 10 and 1 Corinthians 15)
    This is the biblical gospel to eternal life. *All without Christ will perish in their sins in Hell, and, ultimately, in the Lake of Fire, for all eternity. Never ending torment. (Romans **3:23**, Hebrews **4:13**, Romans **6:23**, Revelations 20).*
    The gospel is not just a religious action. No, it changes your entire life and you NO LONGER live for yourself but live to serve God alone. Jesus said you MUST worship God in spirit and truth. John 4:24
    (Critical & Essential Note: To understand God's word, you have to have faith that God exists (Hebrews 11:6); have to repent and open up to God. God will give you wisdom and understanding (and a new life/being born again) if you sincerely repent and let Him help you, for He is the Word of God (John 1:1). If you don't, you will NEVER understand it in God's truth. This statement comes from the experience of a true follower of Christ whose fruit is complete obedience to the full and complete Gospel and God, by God's standards in His Word. Only then will you truly understand the Word of God/Bible. This is part of the many reasons why knowing, having, and sharing the complete gospel is so important for the true followers of Christ, and for those who don't know the things of God, unbelievers, and false christian converts.)
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    Man made traditions, man's flawed theologies, etc has made God's commandments of none effect/null/void/useless! (Matthew 15, Mark 7:3-9, Jeremiah 10:1-5, Deuteronomy 5:32-33, and many other verses). Repent, be born again, obey God in holiness/obedience, and endure until the end, or Jesus will deny you! (Matthew 7:13-29 (v.23)).
    Beware lest any man spoil you through philosophy and vain deceit, after the tradition of men, after the rudiments of the world, and not after Christ. (Colossians 2:8)
    There are some specific exceptions: In Luke 23:39-43 The thief on the cross saw Jesus as the Christ. The thief said that he was deserving of the death they were being put through, but said Jesus did not deserve it at all. He saw that he was deserving of death and changed his mind about himself, that he was a sinner and deserved what he was getting. Jesus, in His grace and mercy, forgave this thief and, in turn, the thief was given eternal life. (And Jesus said unto him, Verily I say unto thee, Today shalt thou be with me in paradise. (Luke 23:43)) Likewise, when someone who is going to perish or has admitted they were sinners and called out to Jesus to forgive them, He will forgive them if they really mean it. God knows the heart and thoughts of every man. (Matthew 9:4)
    And Jesus said unto him, Verily I say unto thee, Today shalt thou be with me in paradise. (Luke 23:43)
    HOWEVER: There is no excuse if someone has (or has had) access to the bible in one way or another (Americans, Europeans, anyone having access to the internet, physical bible, etc). God expects all those who have such resources to use them to gain more understanding of Him and His Word, etc. NO EXCUSES! God knows both the inside and outside of a person. He knows all of your heart and all of your ways. Because of this situation, if we don’t obey, we will have our portion with the unbelievers, and that is ultimately in the lake of fire. (Read Luke 12) So do not practice sin, or this will be your destination.
    God has no pleasure in the death of the wicked (Ezekiel 18:23, 32, Ezekiel 33:11); why die when you can be forgiven and follow God in every facet of your life and live for eternity in God's Kingdom? God is not willing that anyone should perish, but come to repentance, and live (2 Peter 3:9). But you still have a choice....
    Bottom line: You are either righteous and walking with God or wicked following satan, the devil. (1 John 3). You will either live for all eternity with Christ because you lived for God and endured until the end, or perish in eternal torment in hell, then the lake of fire because you did not follow God when you had been given the opportunity to have faith in the death and resurrection of Christ (That Christ is God, died for you), repent and change your mind and ways to God's ways, have received a new heart and mind to serve God in every facet of your life, obey God in holiness, and endure until the end. God will be the just and perfect judge of all this. So repent and live for God so you can live for eternity with Him in His Heavenly Kingdom, will you? The exceptions do apply; God is also merciful. God's word cannot contradict itself, for it is inspired and breathed by God Himself (2 Timothy 3:16). God cannot contradict Himself. He is not the author of confusion (1 Corinthians 14:33), nor can He lie (Numbers 23:19, 1 Samuel 15:29, Psalm 89:35, Hebrews 6:18).
    If you repent (and are seeking assistance), looking for more information, visit and
    Read your bibles with good, biblical discernment! That's the most important thing! Obey The Gospel, Read God’s Word, ask God to help you, discern, judge biblically and living godly according to His Holy Word (etc)!
    (Note: No replies to the replies to this comment will be given. You may contact us via email on our web pages. Thank you for your time reading this.)

  • Paige Barlow
    Paige Barlow 2 months ago

    will this make me pass my bio 110 exam tomorrow

  • Abdulhafz Mohammed
    Abdulhafz Mohammed 2 months ago

    Why no find translation into Arabic language.😢

  • Natey Boi
    Natey Boi 2 months ago

    these guys would be like the best teachers

  • Tiffany Co
    Tiffany Co 3 months ago

    hey amoeba sisters! do you mind answering this question for me? what is retrovirus?

  • Ben Nguyen
    Ben Nguyen 3 months ago

    So do I understand correctly that the lytic cycle is how a standard influenza virus replicates, while the lysogenic cycle is how a retro-virus does it? In the former, some of the cell's ribosomes are hijacked and make virus genes/proteins exclusively, while in the latter, the virus dna is inserted into the cell's normal dna?
    Is it known *how* an external trigger causes a (virus) gene to be expressed to make a protein/RNA? For example, I've read methylation is the epigenetic tool to keep a gene in the 'off' position, but there are proteins (ex. SIRT) that are doing the monitoring?

  • greencapzelda
    greencapzelda 3 months ago +1


  • Bektas Yalcin
    Bektas Yalcin 3 months ago

    Am i the only one who knows Doctor Bacteriophage?

  • Aziza B
    Aziza B 3 months ago

    Amazing 👏🏻👏🏻👏🏻

  • Sem Rappange
    Sem Rappange 3 months ago

    Don’t forget viruses can also infect other viruses. Nothing important just funny.

  • Alucard Lord
    Alucard Lord 3 months ago

    1.How does ebola alive when virus are considered non living things
    2.And how do viruses die? When like i said it is non living things
    3.Do you mean they just swicth to deactivate mode? For ex. The virus is outside the body for years,, do they just deactivate?
    4. Or they can be activated again after of long years of being deactivated?

  • Leeann Hustead
    Leeann Hustead 3 months ago

    What diseases viruses cause during the lysogenic cycle and which kinds of viruses do the lysogenic cycle

  • Soulinite
    Soulinite 3 months ago

    You got the virus replication wrong, you did a bacteriophage which do NOT affect humans

    • Amoeba Sisters
      Amoeba Sisters  3 months ago

      We mention the many shapes that viruses come in...and then state at 1:20 that the bacteriophage, which affects bacteria, is our favorite to draw! This is a common example virus type to show for general virus replication steps. However, if you're looking for a specific example of a virus that affects humans, there is one discussed towards the end of the video.

    GD MUGZ THE GREAT 3 months ago

    HAHAHAHA, the ecosystem will die if you release a viral infection for pests

  • Valerie Valdivia
    Valerie Valdivia 3 months ago

    My favorite biology channel to watch , thank you for your existence.

  • Isabella Gomez
    Isabella Gomez 3 months ago

    Love this video it really helps like lots.😊😊

  • Mykaela Gomez
    Mykaela Gomez 3 months ago

    these video were so helpful to me when I was taking biology

  • Roasted Carot
    Roasted Carot 3 months ago

    if the amoeba sisters are both cells and were examining viruses at a close range, then how didnt either one get infected by any viruses trying to reproduce?

    this lore is W H A C K