Polymerase Chain Reaction | Easy Animated Biology

This is how PCR works: the idea Kary Mullis had while driving at night, which earned him a Nobel Prize. The 2026 edition of my 2018 PCR video, now in English: new animation and a revised script. In this video, you'll learn: The five ingredients of PCR and what each one does Why polymerase needs primers and why the 5′ → 3′ direction matters What a thermal cycler does: initial heating, hot-start polymerases, and the three steps of each cycle Why Taq polymerase survives the heat, and what Yellowstone has to do with it How we reach, in theory, a billion copies, and when the first exact amplicons appear Why every reaction reaches a plateau How to check whether PCR worked: agarose gel, DNA ladder, negative control, and ethidium bromide Credits Photo of Kary B. Mullis: courtesy of Kary Mullis. Thermus aquaticus micrograph: Agriculture and Agri-Food Canada / Diane Montpetit, via Wikimedia Commons. Sound effects: Pixabay. Music: original, composed for this video. Animation: original. References cited on screen K. Mullis et al. (1986). https://doi.org/10.1101/sqb.1986.051.... Thomas D. Brock, Hudson Freeze (1969). https://doi.org/10.1128/jb.98.1.289-2... Randall K. Saiki et al. (1988). https://doi.org/10.1126/science.2448875 References supporting the video Randall K. Saiki et al. (1985). https://doi.org/10.1126/science.2999980 A Chien et al. (1976). https://doi.org/10.1128/jb.127.3.1550... F C Lawyer et al. (1993). https://doi.org/10.1101/gr.2.4.275 Wei Yang et al. (2006). https://doi.org/10.1016/j.molcel.2006... W. Rychlik et al. (1990). https://doi.org/10.1093/nar/18.21.6409 Quin Chou et al. (1992). https://doi.org/10.1093/nar/20.7.1717 Natasha Paul et al. (2010). https://doi.org/10.1007/978-1-60761-6... Stephen A Bustin et al. (2009). https://doi.org/10.1373/clinchem.2008... Peter Kainz (2000). https://doi.org/10.1016/s0167-4781(00... Linda Jansson, Johannes Hedman (2019). https://doi.org/10.1016/j.bdq.2019.10... Pei Yun Lee et al. (2012). https://doi.org/10.3791/3923 Shri C. Jain, Henry M. Sobell (1984). https://doi.org/10.1080/07391102.1984... John Olmsted, David R. Kearns (1977). https://doi.org/10.1021/bi00635a022 Follow me on social media and subscribe: the goal is to reach a hundred thousand subscribers. Keep learning and keep becoming your best self. #PCR #MolecularBiology #Biotechnology Chapters 0:00 A sentence in an entire library 0:24 Kary Mullis: the idea on the road 0:58 The five ingredients 1:37 Primers: where copying begins 2:29 The thermal cycler and hot-start polymerases 2:59 The three steps of each cycle 3:48 Taq: the enzyme from Yellowstone 4:06 The chain part 4:40 2ⁿ: up to a billion copies 5:04 The plateau: why the reaction slows down 5:44 Did it work? The agarose gel 6:42 Ethidium bromide and UV light 7:04 The PCR family and goodbye