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  • Transcription: How mRNA Helped Save Lives: Crash Course Biology #34

    You’ve probably heard of mRNA, thanks to the COVID-19 vaccine. But what is mRNA exactly? In this episode of Crash Course Biology, we learn about the role of messenger RNA in living things and how it decodes our DNA instruction manual through transcription.

    Introduction: mRNA Vaccines 00:00
    Messenger RNA 1:21
    Transcription 3:48
    Processing & Splicing 5:05
    The Central Dogma 7:00
    Alternative Splicing 8:39
    Review & Credits 10:46

    This series was produced in collaboration with HHMI BioInteractive, committed to empowering educators and inspiring students with engaging, accessible, and quality classroom resources. Visit https://BioInteractive.org/CrashCourse for more information.

    Are you an educator looking for what NGSS Standards are covered in this episode? Check out our Educator Standards Database for Biology here: https://www.thecrashcourse.com/biologystandards

    Check out our Biology playlist here: https://www.youtube.com/playlist?list=PL8dPuuaLjXtPW_ofbxdHNciuLoTRLPMgB

    Watch this series in Spanish on our Crash Course en Español channel here: https://www.youtube.com/playlist?list=PLkcbA0DkuFjWQZzjwF6w_gUrE_5_d3vd3

    Sources: https://docs.google.com/document/d/1GLDtAXE6ekg4Chk2qN3TYbNt0pJbyaHqTqRd6QY8pd4/edit?usp=sharing

    ***

    Crash Course is on Patreon! You can support us directly by signing up at http://www.patreon.com/crashcourse

    Thanks to the following patrons for their generous monthly contributions that help keep Crash Course free for everyone forever:
    Leah H., David Fanska, Andrew Woods, DL Singfield, Ken Davidian, Stephen Akuffo, Toni Miles, Steve Segreto, Kyle & Katherine Callahan, Laurel Stevens, Burt Humburg, Perry Joyce, Scott Harrison, Mark & Susan Billian, Alan Bridgeman, Breanna Bosso, Matt Curls, Jennifer Killen, Jon Allen, Sarah & Nathan Catchings, team dorsey, Bernardo Garza, Trevin Beattie, Eric Koslow, Indija-ka Siriwardena, Jason Rostoker, Siobhán, Ken Penttinen, Nathan Taylor, Barrett & Laura Nuzum, Les Aker, William McGraw, Vaso, ClareG, Rizwan Kassim, Constance Urist, Alex Hackman, Pineapples of Solidarity, Katie Dean, Stephen McCandless, Wai Jack Sin, Ian Dundore, Caleb Weeks
    __

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    18 min
  • Vision: Crash Course Anatomy and Physiology #18

    Next stop in our tour of your sensory systems? VISION. With a little help from an optical illusion, we take a look inside your eyes to try to figure out how your sense of vision works -- and how it can be tricked.

    Pssst... we made flashcards to help you review the content in this episode! Find them on the free Crash Course App!
    Download it here for Apple Devices: https://apple.co/3d4eyZo
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    Chapters:
    Introduction: Optical Illusions 00:00
    How Does Light Work? 1:31
    Structure of the Eye 2:31
    Layers of the Eye: Fibrous, Vascular, and Inner Layers 3:33
    The Retina 4:56
    Rods and Cones 6:07
    How do Optical Illusions Work? 7:15
    Review 8:33
    Credits 9:14

    ***
    Thanks to the following Patrons for their generous monthly contributions that help keep Crash Course free for everyone forever:

    Mark Brouwer, Jan Schmid, Steve Marshall, Anna-Ester Volozh, Sandra Aft, Brad Wardell, Christian Ludvigsen, Robert Kunz, Jason, A Saslow, Jacob Ash, Jeffrey Thompson, Jessica Simmons, James Craver, Simun Niclasen, SR Foxley, Roger C. Rocha, Nevin, Spoljaric, Eric Knight, Elliot Beter, Jessica Wode, Sofie Harning, Sour Bags & Totes, Don Phillips, Christian Dodson, Christian Dodson (once again), Christian Dodson (again), Christian Dodson (NO EDGE), tuseroni, Amy Guerrero


    ***
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    14 min
  • Doing Solids: Crash Course Chemistry #33

    In which Hank blows our minds with the different kinds of solids out there and talks about why they're all different and have different properties. Today, you'll learn about amorphous and crystalline solids, types of crystalline solids, types of crystalline atomic solids, properties of each type of solid, and that the properties depend on the bond types.

    Pssst... we made flashcards to help you review the content in this episode! Find them on the free Crash Course App!

    Download it here for Apple Devices: https://apple.co/3d4eyZo
    Download it here for Android Devices: https://bit.ly/2SrDulJ

    --
    Table of Contents

    Amorphous and Crystalline Solids 1:27
    Types of Crystalline Solids 4:07
    Types of Crystalline Atomic Solids 5:17
    Properties of Each Type of Solid 4:16
    Properties Depend on Bond Types 6:17
    --

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    14 min
  • Translation: How RNA Gets Translated into Protein Power: Crash Course Biology #35

    How does the information from mRNA turn into a protein? It all comes down to translation, where nucleotides are translated into a chain of amino acids. In this episode of Crash Course Biology, we’ll cover codon-reading ribosomes, tRNA delivery trucks, and scientists who are using what they know about translation to save lives.

    Introduction: Making Proteins 00:00
    DNA & mRNA 1:13
    How Translation Works 2:16
    Peptides & Polypeptides 6:43
    Why Proteins Matter 7:07
    Dr. Katalin Karikó 9:26
    Review & Credits 11:37

    This series was produced in collaboration with HHMI BioInteractive, committed to empowering educators and inspiring students with engaging, accessible, and quality classroom resources. Visit https://BioInteractive.org/CrashCourse for more information.

    Are you an educator looking for what NGSS Standards are covered in this episode? Check out our Educator Standards Database for Biology here: https://www.thecrashcourse.com/biologystandards

    Check out our Biology playlist here: https://www.youtube.com/playlist?list=PL8dPuuaLjXtPW_ofbxdHNciuLoTRLPMgB

    Watch this series in Spanish on our Crash Course en Español channel here: https://www.youtube.com/playlist?list=PLkcbA0DkuFjWQZzjwF6w_gUrE_5_d3vd3

    Sources: https://docs.google.com/document/d/1GLDtAXE6ekg4Chk2qN3TYbNt0pJbyaHqTqRd6QY8pd4/edit?usp=sharing

    ***

    Crash Course is on Patreon! You can support us directly by signing up at http://www.patreon.com/crashcourse

    Thanks to the following patrons for their generous monthly contributions that help keep Crash Course free for everyone forever:
    Leah H., David Fanska, Andrew Woods, DL Singfield, Ken Davidian, Stephen Akuffo, Toni Miles, Steve Segreto, Kyle & Katherine Callahan, Laurel Stevens, Burt Humburg, Perry Joyce, Scott Harrison, Mark & Susan Billian, Alan Bridgeman, Breanna Bosso, Matt Curls, Jennifer Killen, Jon Allen, Sarah & Nathan Catchings, team dorsey, Bernardo Garza, Trevin Beattie, Eric Koslow, Indija-ka Siriwardena, Jason Rostoker, Siobhán, Ken Penttinen, Nathan Taylor, Barrett & Laura Nuzum, Les Aker, William McGraw, Vaso, ClareG, Rizwan Kassim, Constance Urist, Alex Hackman, Pineapples of Solidarity, Katie Dean, Stephen McCandless, Wai Jack Sin, Ian Dundore, Caleb Weeks
    __

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    19 min
  • The Roaring 20's: Crash Course US History #32

    In which John Green teaches you about the United States in the 1920s. They were known as the roaring 20s, but not because there were lions running around everywhere. In the 1920s, America's economy was booming, and all kinds of social changes were in progress. Hollywood, flappers, jazz, there was all kinds of stuff going on in the 20s. But as usual with Crash Course, things were about to take a turn for the worse. John will teach you about the Charleston, the many Republican presidents of the 1920s, laissez-faire capitalism, jazz, consumer credit, the resurgent Klan, and all kinds of other stuff.

    Hey teachers and students - Check out CommonLit's free collection of reading passages and curriculum resources to learn more about the events of this episode. The Roaring Twenties was characterized by great highs: https://www.commonlit.org/texts/the-roaring-twenties
    However, the Roaring Twenties ended with the country's most tragic low, the Great Depression: https://www.commonlit.org/texts/the-great-depression

    Chapters:
    Introduction: The 1920s 00:00
    The Roaring 20's 0:46
    Laissez-Faire Capitalism 1:14
    Warren G. Harding's Corrupt Administration 1:55
    Automobiles & Manufacturing 2:24
    Leisure & Pop Culture 3:29
    The Birth of the American Film Industry 3:57
    Consumer Debt and the "American Standard of Living" 4:23
    Contemporary Celebrity Culture 4:44
    Mystery Document 5:33
    Flappers & Women's Liberation 6:24
    Wealth Disparities in the 1920s 7:12
    The Supreme Court's Juris Prudence of Civil Liberties 8:50
    Hyper-Patriotism and White Supremacy 9:38
    Immigration Restriction Laws 10:15
    The Scopes Trial & Teaching Evolution 11:13
    The Legacy of the 1920s 12:04
    Credits 12:36

    Crash Course is on Patreon! You can support us directly by signing up at http://www.patreon.com/crashcourse

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    19 min
  • The First Fraction of a Second | Crash Course Pods: The Universe #1

    Head to https://policygenius.com/crashcourse to get your free life insurance quotes and see how much you could save.

    Dr. Katie Mack teaches John Green about the beginning of the Universe - including that we are not just made of stardust; we are also made of Big Bang stuff, with pieces of us directly born in the vast, first cacophony.

    Chapters
    00:00 - Introduction
    4:00 - There Shouldn’t Be Stuff
    8:53 - The Big Bang Theory
    21:28 - We’re Not Sure About The Singularity
    32:00 - Cosmic Inflation
    36:26 - The First Second
    38:43 - The First Two Minutes
    46:48 - Outro

    ***
    Crash Course is on Patreon! You can support us directly by signing up at http://www.patreon.com/crashcourse

    Thanks to the following patrons for their generous monthly contributions that help keep Crash Course free for everyone forever:
    Leah H., David Fanska, Andrew Woods, DL Singfield, Ken Davidian, Stephen Akuffo, Toni Miles, Steve Segreto, Kyle & Katherine Callahan, Laurel Stevens, Burt Humburg, Perry Joyce, Scott Harrison, Mark & Susan Billian, Alan Bridgeman, Breanna Bosso, Matt Curls, Jennifer Killen, Jon Allen, Sarah & Nathan Catchings, team dorsey, Bernardo Garza, Trevin Beattie, Eric Koslow, Indija-ka Siriwardena, Jason Rostoker, Siobhán, Ken Penttinen, Nathan Taylor, Barrett & Laura Nuzum, Les Aker, William McGraw, Vaso, ClareG, Rizwan Kassim, Constance Urist, Alex Hackman, Pineapples of Solidarity, Katie Dean, Stephen McCandless, Wai Jack Sin, Ian Dundore, Caleb Weeks
    __

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    57 min
  • The Deadliest Infectious Disease of All Time | Crash Course Lecture

    Tuberculosis is often thought of as an old-timey disease, but in reality, it continues to kill over a million and a half people per year, despite its known cure. How did we get here, to a world where decades of work toward a cure stalled in its dissemination around the globe? And how can understanding the history of TB point us toward a different future? If you’ve been following author and TB-hater John Green in any way for the last year or so, this video is the deep dive you’ve been waiting for…

    TB Fighters: You can learn more about the TB Fighters Community at https://tbfighters.org

    This lecture was produced thanks to the generosity of the Crash Course audience, including those who fund us on Patreon, who’ve purchased Crash Course coins, and who share Crash Course with others. Your support lets us experiment with new formats, cover lesser-known topics, and go deeper than we ever have before. Thank you!

    Sources: https://docs.google.com/document/d/1C8jRj6cE50pnoDyLQVGYhCWyazHz4vC-TC_KXC6tnak/edit#heading=h.4kgrhaj5zoui

    Chapters:
    The Deadliest Infectious Disease of All Time 00:00
    Tuberculosis is Weird 3:36
    "Man Got to Tell Himself He Understand" 7:05
    The Allure of Consumption 14:46
    The White Man's Plague 21:07
    Treatments and the Cure 27:29
    Where the Drugs Are Not 34:06
    A Fundamental Mistrust 36:48
    The World We Choose 45:34


    The surprising history - and current dilemma - of TB


    ***
    Crash Course is on Patreon! You can support us directly by signing up at http://www.patreon.com/crashcourse

    Thanks to the following patrons for their generous monthly contributions that help keep Crash Course free for everyone forever:
    Leah H., David Fanska, Andrew Woods, Sean Saunders, DL Singfield, Ken Davidian, Stephen Akuffo, Toni Miles, Steve Segreto, Kyle & Katherine Callahan, Laurel Stevens, Burt Humburg, Perry Joyce, Scott Harrison, Mark & Susan Billian, Alan Bridgeman, Breanna Bosso, Matt Curls, Jennifer Killen, Jon Allen, Sarah & Nathan Catchings, team dorsey, Bernardo Garza, Trevin Beattie, Eric Koslow, Indija-ka Siriwardena, Jason Rostoker, Siobhán, Ken Penttinen, Nathan Taylor, Barrett & Laura Nuzum, Les Aker, William McGraw, Vaso, ClareG, Rizwan Kassim, Constance Urist, Alex Hackman, Pineapples of Solidarity, Katie Dean, Stephen McCandless, Thomas Greinert, Wai Jack Sin, Ian Dundore, Caleb Weeks
    __

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    59 min
  • Chemoselectivity and Protecting Groups: Crash Course Organic Chemistry #33

    Things have been getting more and more complicated here in Crash Course Organic Chemistry, and as we deal with more complex molecules, parts of molecules we don’t want to react will start reacting along with the parts that we do. Luckily, we have protecting groups, which act like a chemical disguise and help us control how molecules react. In this episode, we’ll look at what makes a good protecting group, as well as identify some good protecting groups for different functional groups. We’ll also see what role protecting groups play in the synthesis of penicillin!

    Series Penicillin References:
    Nicolaou, K. C., & Sorensen, E. J. (1996). Classics in total synthesis: targets, strategies, methods. John Wiley & Sons.
    Sheehan, J. C. (1982). The enchanted ring: the untold story of penicillin.
    Primary literature for Sheehan’s penicillin synthesis: Sheehan, J.C. & Izzo, P.T. J. Am. Chem. Soc. 1948, 70, 1985; Sheehan, J.C. & Izzo, P.T. J. Am. Chem. Soc. 1949, 71, 4059; Sheehan, J.C. & Bose A.K. J. Am. Chem. Soc. 1950, 72, 5158; Sheehan, J.C., Buhle, E.L, Corey E.J., Laubach, G.D. & Ryan J.J. J. Am. Chem. Soc. 1950, 72, 3828; Sheehan, J.C. & Laubach, G.D. J. Am. Chem. Soc. 1951, 73, 4376; Sheehan, J.C. & Hoff, D.R. J. Am. Chem. Soc. 1957, 79, 237; Sheehan, J.C. & Corey E.J. J. Am. Chem. Soc. 1951, 73, 4756

    Series Sources:
    Brown, W. H., Iverson, B. L., Ansyln, E. V., Foote, C., Organic Chemistry; 8th ed.; Cengage Learning, Boston, 2018.
    Bruice, P. Y., Organic Chemistry, 7th ed.; Pearson Education, Inc., United States, 2014.
    Clayden, J., Greeves, N., Warren., S., Organic Chemistry, 2nd ed.; Oxford University Press, New York, 2012.
    Jones Jr., M.; Fleming, S. A., Organic Chemistry, 5th ed.; W. W. Norton & Company, New York, 2014.
    Klein., D., Organic Chemistry; 1st ed.; John Wiley & Sons, United States, 2012.
    Louden M., Organic Chemistry; 5th ed.; Roberts and Company Publishers, Colorado, 2009.
    McMurry, J., Organic Chemistry, 9th ed.; Cengage Learning, Boston, 2016.
    Smith, J. G., Organic chemistry; 6th ed.; McGraw-Hill Education, New York, 2020.
    Wade., L. G., Organic Chemistry; 8th ed.; Pearson Education, Inc., United States, 2013.

    ***
    Watch our videos and review your learning with the Crash Course App!
    Download here for Apple Devices: https://apple.co/3d4eyZo
    Download here for Android Devices: https://bit.ly/2SrDulJ

    Crash Course is on Patreon! You can support us directly by signing up at http://www.patreon.com/crashcourse

    Thanks to the following patrons for their generous monthly contributions that help keep Crash Course free for everyone forever:

    Toni Miles, Oscar Pinto-Reyes, Erin Nicole, Steve Segreto, Michael M. Varughese, Kyle & Katherine Callahan, Laurel A Stevens, Evan Lawrence Henderson, Vincent, Michael Wang, Krystle Young, Michael Dowling, Alexis B, Rene Duedam, Burt Humburg, Aziz, DAVID MORTON HUDSON, Perry Joyce, Scott Harrison, Mark & Susan Billian, JJurong, Eric Zhu, Alan Bridgeman, Rachel Creager, Jennifer Smith, Matt Curls, Tim Kwist, Jonathan Zbikowski, Jennifer Killen, Sarah & Nathan Catchings, Brandon Westmoreland, team dorsey, Trevin Beattie, Divonne Holmes à Court, Eric Koslow, Jennifer Dineen, Indika Siriwardena, Khaled El Shalakany, Jason Rostoker, Shawn Arnold, Siobhán, Ken Penttinen, Nathan Taylor, William McGraw, Andrei Krishkevich, ThatAmericanClare, Rizwan Kassim, Sam Ferguson, Alex Hackman, Eric Prestemon, Jirat, Katie Dean, TheDaemonCatJr, Wai Jack Sin, Ian Dundore, Matthew, Justin, Jessica Wode, Mark, Caleb Weeks
    __

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    17 min
  • Conjugation and UV-Vis Spectroscopy: Crash Course Organic Chemistry #41

    Carrots get their orange-y color from, you guessed it, an organic chemical. This chemical, called beta carotene, gets its pigment from its conjugated electron system. We’ve talked some already about conjugation, but in this episode of Crash Course Organic Chemistry we’ll go even deeper and look at how conjugation stabilizes molecules and how p orbitals can overlap to form pi molecular orbitals of different energy levels. Plus we’ll learn what UV spectroscopy can show us about conjugated molecules.

    Episode Sources:
    Semba, R.D., 2012. On the ‘discovery’ of vitamin A. Annals of nutrition and metabolism, 61(3), pp.192-198.
    Webbook.nist.gov. 2021. 1,4-Pentadiene. [online] Available at: https://webbook.nist.gov/cgi/cbook.cgi?ID=C591935&Units=SI&Mask=8#Thermo-React

    Series Sources:
    Brown, W. H., Iverson, B. L., Ansyln, E. V., Foote, C., Organic Chemistry; 8th ed.; Cengage Learning, Boston, 2018.
    Bruice, P. Y., Organic Chemistry, 7th ed.; Pearson Education, Inc., United States, 2014.
    Clayden, J., Greeves, N., Warren., S., Organic Chemistry, 2nd ed.; Oxford University Press, New York, 2012.
    Jones Jr., M.; Fleming, S. A., Organic Chemistry, 5th ed.; W. W. Norton & Company, New York, 2014.
    Klein., D., Organic Chemistry; 1st ed.; John Wiley & Sons, United States, 2012.
    Louden M., Organic Chemistry; 5th ed.; Roberts and Company Publishers, Colorado, 2009.
    McMurry, J., Organic Chemistry, 9th ed.; Cengage Learning, Boston, 2016.
    Smith, J. G., Organic chemistry; 6th ed.; McGraw-Hill Education, New York, 2020.
    Wade., L. G., Organic Chemistry; 8th ed.; Pearson Education, Inc., United States, 2013.

    ***
    Watch our videos and review your learning with the Crash Course App!
    Download here for Apple Devices: https://apple.co/3d4eyZo
    Download here for Android Devices: https://bit.ly/2SrDulJ

    Crash Course is on Patreon! You can support us directly by signing up at http://www.patreon.com/crashcourse

    Thanks to the following patrons for their generous monthly contributions that help keep Crash Course free for everyone forever:
    Dave Freeman, Hasan Jamal, DL Singfield, Jeremy Mysliwiec, Shannon McCone, Amelia Ryczek, Ken Davidian, Stephen Akuffo, Toni Miles, Erin Switzer, Steve Segreto, Michael M. Varughese, Kyle & Katherine Callahan, Laurel A Stevens, Vincent, Michael Wang, Stacey Gillespie, Jaime Willis, Krystle Young, Michael Dowling, Alexis B, Burt Humburg, Aziz Y, DAVID MORTON HUDSON, Perry Joyce, Scott Harrison, Mark & Susan Billian, Junrong Eric Zhu, Alan Bridgeman, Rachel Creager, Jennifer Smith, Matt Curls, Tim Kwist, Jonathan Zbikowski, Jennifer Killen, Sarah & Nathan Catchings, Brandon Westmoreland, team dorsey, Trevin Beattie, Divonne Holmes à Court, Eric Koslow, Jennifer Dineen, Indika Siriwardena, Khaled El Shalakany, Jason Rostoker, Shawn Arnold, Siobhán, Ken Penttinen, Nathan Taylor, Les Aker, William McGraw, Andrei Krishkevich, ThatAmericanClare, Rizwan Kassim, Sam Ferguson, Alex Hackman, Jirat, Katie Dean, NileMatotle, Wai Jack Sin, Ian Dundore, Justin, Jessica Wode, Mark, Caleb Weeks
    __

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    19 min
  • Crash Course Chemistry: Outtakes #2

    In which Hank has trouble doing and saying things.

    Crash Course is on Patreon! You can support us directly by signing up at http://www.patreon.com/crashcourse

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    13 min

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