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  • Simple Animals: Sponges, Jellies, and Octopuses - Crash Course Biology #22

    Hank introduces us to the "simplest" of the animals, complexity-wise: beginning with sponges (whose very inclusion in the list as "animals" has been called into question because they are so simple) and finishing with the most complex molluscs, octopuses and squid. We differentiate them by the number of tissue layers they have, and by the complexity of those layers.

    Table of Contents:
    1) Porifera 1:33
    2) Cnidaria 2:36
    a) Diploblasts 2:48
    3) Platyhelminthes 3:33
    a) Triploblasts 3:56
    b) Coelom 4:36
    4) Biolography 5:36
    5) Nematoda 7:26
    6) Rotifera 7:57
    7) Molusca 8:33

    References:
    http://www.ucmp.berkeley.edu/cnidaria/cnidaria.html http://www.slate.com/articles/health_and_science/science/2008/06/how_smart_is_the_octopus.html
    http://en.wikipedia.org/wiki/File:Dicrocoelium_LifeCycle.gif
    http://entnemdept.ufl.edu/creatures/nematode/soil_nematode.htm
    http://soils.usda.gov/sqi/concepts/soil_biology/nematodes.html
    http://www.eurekalert.org/pub_releases/2010-08/uoc--goa080410.php
    http://www.ucmp.berkeley.edu/cambrian/cambrian.php
    http://www.insidescience.org/news-service/1-2615
    http://www.wormbook.org/chapters/www_genomevol/genomevol.pdf
    http://www.cartage.org.lb/en/themes/sciences/zoology/animalclassification/Polygenetic/phylogenetictree/phylogenetictree.htm
    http://www.esu.edu/~milewski/intro_biol_two/lab_9_porifera_cnidaria/Cnidaria.html
    http://comenius.susqu.edu/biol/202/animals/protostomes/default.htm

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    17 min
  • Race, Ethnicity, and the Cultural Landscape: Crash Course Geography #29

    Sometimes culture can seem invisible like when we're surrounded by signals that tell us we're with others who are like us, but if we live or travel somewhere where the traits that define social norms are not our traits, culture can suddenly seem everywhere. In the next few episodes, we're going to start exploring the fundamental aspects of culture and how those with and without power are affected by culture, from cultural mixing to cultural violence. We'll also discuss the differences between race, ethnicity, and culture, and help you can spot the warning signs that often lead to xenophobia, racism, and genocide.

    Watch our videos and review your learning with the Crash Course App!
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    Shannon McCone, Amelia Ryczek, Ken Davidian, Brian Zachariah, Stephen Akuffo, Toni Miles, Oscar Pinto-Reyes, Erin Nicole, Steve Segreto, Michael M. Varughese, Kyle & Katherine Callahan, Laurel A Stevens, Vincent, Michael Wang, Stacey Gillespie, Jaime Willis, Krystle Young, Michael Dowling, Alexis B, Rene Duedam, Burt Humburg, Aziz, 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, William McGraw, Andrei Krishkevich, ThatAmericanClare, Rizwan Kassim, Sam Ferguson, Alex Hackman, Jirat, Katie Dean, neil matatall, TheDaemonCatJr, Wai Jack Sin, Ian Dundore, Matthew, Justin, Jessica Wode, Mark, Caleb Weeks
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    #CrashCourse #Geography #Culture

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    18 min
  • Native Languages and The Indian Education Act: Ep 21 of Crash Course Native American History

    It’s time to save Native languages—before it’s too late. In this episode of Crash Course Native American History, we dig into the ways Native languages were destroyed and the resilient ways tribes are bringing them back to life.

    Introduction: "Never Alone" 00:00
    The State of Native Language 0:35
    Revealing Native Culture 1:40
    Colonization & Boarding Schools 3:42
    Language Revitalization 7:00
    Review & Credits 9:04

    Sources:
    https://docs.google.com/document/d/1g1BpQk_2qXtFeQBffoAT-rrogcKRaA2eNjeRCpmCrJ8/edit?usp=sharing

    Want to know more about how this series was made? Learn more here: https://docs.google.com/document/d/17yp3u28s40TdjyrJniIf4U9YA8wPtvQ1g1B-HSHQ2Q4/edit?tab=t.0#heading=h.6vtzps565m2

    ***
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    oranjeez, Jason Terpstra, Chelsea S, Alan Bridgeman, Roger Harms, DexcilaDou, Krystle Young, Allison Wood, Stephen Akuffo, Katrix , Gina Mancuso, Shruti S, Martin G. Diller, Matthew Fredericksen, Brandon Thomas, Breanna Bosso, Ken Davidian, UwU, Jennifer Wiggins-Lyndall, Samantha, David Fanska, Kristina D Knight, Andrew Woods, Elizabeth LaBelle, SpaceRangerWes, Matt Curls, Quinn Harden, EllenBryn, Johnathan Williams, Leah H., Laurel Stevens, Steve Segreto, Michael Maher, Liz Wdow, Toni Miles, Perry Joyce, Evan Nelson, Katie Hoban, Mitch Gresko, Kevin Knupp, Kyle & Katherine Callahan, Tanner Hedrick, Emily Beazley, Jack Hart, Rie Ohta, Dalton Williams, Scott Harrison, Barbara Pettersen, AThirstyPhilosopher ., Thomas Sully, Bernardo Garza, Jason Rostoker, Rizwan Kassim, Indija-ka Siriwardena, Emily T, Ian Dundore, Joseph Ruf, Alex Hackman, Thomas, Constance Urist, team dorsey, Stephen McCandless, Triad Terrace, Erminio Di Lodovico, Evol Hong, Luke Sluder, Eric Koslow, Katie Dean, Tandy Ratliff, Jennifer Killen, Jason Buster, Trevin Beattie, Wai Jack Sin, Caleb Weeks, Nathan Taylor, Siobhán, Les Aker, Barrett Nuzum, John Lee, Ken Penttinen, Sarah & Nathan Catchings, Pietro Gagliardi, ClareG, Duncan W Moore IV
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    15 min
  • Charles V and the Holy Roman Empire: Crash Course World History #219

    In which John Green teaches you about the Holy Roman Empire by teaching you about Charles V. Charles Hapsburg was the Holy Roman Emperor, but he was also the King of Spain. And the King of Germany. And the King of Italy and the Lord of the Netherlands and Count Palatine of Burgundy. In short, Charles was runnin' thangs in much of the world during his reign. Charles ruled a lot of countries, and he was also known for encouraging intellectual discourse and even spoke out against slavery, in a limited way. So why did he consider himself a failure, and why did he break up the Empire when he abdicated in 1556? Mainly because the Holy Roman Empire didn't work very well. It was huge, and it didn't have any means of directly raising taxes. Plus, it was a pretty crazy time in Europe anyway, and Charles found himself in charge of the Catholic-Church-Endorsed Empire during the time of Martin Luther and the Protestant Reformation. John will teach you a bit about how Charles put the Empire together, and how it fell apart, and even talk a bit about the Diet of Worms.

    This episode was written by Neal Schulz, but we messed up the onscreen credits. Thanks, and great work, Neal.

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    19 min
  • The Renaissance: Was it a Thing? - Crash Course World History #22

    In which John Green teaches you about the European Renaissance. European learning changed the world in the 15th and 16th centuries, but was it a cultural revolution, or an evolution? We'd argue that any cultural shift that occurs over a couple of hundred years isn't too overwhelming to the people who live through it. In retrospect though, the cultural bloom in Europe during this time was pretty impressive. In addition to investigating what caused the Renaissance and who benefitted from the changes that occurred, John will tell you just how the Ninja Turtles got mixed up in all this.

    Chapters:
    Introduction: The Renaissance 00:00
    Themes in Renaissance Art 1:07
    Humanist Scholars of the Renaissance Era 1:48
    When was the Renaissance? 2:52
    Why the Renaissance Happened in Italy 3:23
    Florentine Textiles 5:08
    How Islamic Scholars Helped Create the European Renaissance 6:30
    An Open Letter to Copernicus 7:17
    Why the Renaissance Didn't Happen 8:12
    Credits 10:56

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    17 min
  • Magical Realism and The Latin American Boom: Crash Course Latin American Literature #2

    How did “Latin American literature” come to be? In this episode of Crash Course Latin American Literature, we trace the origins of this region’s stories from the pre-Columbian era all the way to the Boom of the 1960s.

    Introduction: Stories as History 00:00
    Pre-Columbian Literature 0:23
    Poetry & Bello 2:34
    Bolívar 4:37
    The Latin American Boom 6:08
    Gabriel García Márquez 8:04
    Review & Credits 10:57

    Sources: https://docs.google.com/document/d/1eE7g4-k6PD7C6wNBzeJIO8GCDHpoJl8ldDjKyq_2yYg/edit?tab=t.0
    To learn more, check out these videos:

    Christopher Columbus: Columbus, Vasco da Gama, and Zheng He - 15th Century Mariners: Crash Course World History #21 https://youtu.be/NjEGncridoQ?si=hzKIJz7J5yy3MoOB
    K’iche’ People: Water and Classical Civilizations: Crash Course World History 222 https://youtu.be/rP54LFFSZ1Q?si=6jbF2u3xZyYJS9xy
    Simón Bolívar: Latin American Revolutions: Crash Course World History #31 https://youtu.be/ZBw35Ze3bg8?si=E9lh1t6OdfOPrEXm
    One Hundred Years of Solitude: 100 Years of Solitude Part 1: Crash Course Literature 306 https://youtu.be/YWNcCs__vQg?si=69kPZVKUib4XnYmK , 100 Years of Solitude Part 2: Crash Course Literature 307 https://www.youtube.com/watch?v=Hlpv7nKt81A
    Formula fields should be configured in the field menu dropdown


    ***
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    Thanks to the following patrons for their generous monthly contributions that help keep Crash Course free for everyone forever:
    oranjeez, Jason Terpstra, Chelsea S, Alan Bridgeman, Roger Harms, DexcilaDou, Krystle Young, Allison Wood, Stephen Akuffo, Katrix , Gina Mancuso, Shruti S, Martin G. Diller, Matthew Fredericksen, Brandon Thomas, Breanna Bosso, Ken Davidian, UwU, Jennifer Wiggins-Lyndall, Samantha, David Fanska, Kristina D Knight, Andrew Woods, Elizabeth LaBelle, SpaceRangerWes, Matt Curls, Quinn Harden, EllenBryn, Johnathan Williams, Leah H., Laurel Stevens, Steve Segreto, Michael Maher, Liz Wdow, Toni Miles, Perry Joyce, Evan Nelson, Katie Hoban, Mitch Gresko, Kevin Knupp, Kyle & Katherine Callahan, Tanner Hedrick, Emily Beazley, Jack Hart, Rie Ohta, Dalton Williams, Scott Harrison, Barbara Pettersen, AThirstyPhilosopher ., Thomas Sully, Bernardo Garza, Jason Rostoker, Rizwan Kassim, Indija-ka Siriwardena, Emily T, Ian Dundore, Joseph Ruf, Alex Hackman, Thomas, Constance Urist, team dorsey, Stephen McCandless, Triad Terrace, Erminio Di Lodovico, Evol Hong, Luke Sluder, Eric Koslow, Katie Dean, Tandy Ratliff, Jennifer Killen, Jason Buster, Trevin Beattie, Wai Jack Sin, Caleb Weeks, Nathan Taylor, Siobhán, Les Aker, Barrett Nuzum, John Lee, Ken Penttinen, Sarah & Nathan Catchings, Pietro Gagliardi, ClareG, Duncan W Moore IV
    __

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    18 min
  • Comparative Anatomy: What Makes Us Animals - Crash Course Biology #21

    Hank introduces us to comparative anatomy, which studies the similarities and differences in animal anatomy to support the theory of evolution and the shared ancestry of living things.

    References:
    Campbell Biology, 9th ed.
    CliffsAP Biology, 3rd ed.
    Thomas Henry Huxley: http://www.strangescience.net/huxley.htm
    Tissues: http://web.jjay.cuny.edu/~acarpi/NSC/14-anatomy.htm
    Divergence time estimates for the early history of animal phyla...
    http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1689654/

    Table of Contents:
    1) Comparative Anatomy 0:00
    2) Locomotion 1:19
    3) Heterotophy 1:41
    4) Convergent Evolution 2:40
    5) Biolography 3:40
    6) Tissues 6:00
    a) Epithelial Tissue 6:11
    b) Connective Tissue 6:33
    c) Muscle Tissue 7:01
    d) Nerve Tissue 7:14
    7) Organs 7:32
    8) Organ Systems 7:39


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    14 min
  • The Land Back Movement Explained: Ep 22 of Crash Course Native American History

    The Land Back movement is exactly what it sounds like: Native Americans want their land … back. But it’s also a whole lot more than that. In this episode of Crash Course Native American History, we explore what the Land Back movement does, how it works, and what it means for our shared future on this planet.

    Introduction: 1492 Land Back Lane 00:00
    Land Back & Land Acknowledgements 0:40
    Settler Rent 2:00
    The Jemez Pueblo Tribe 3:17
    Environmental Impact 4:14
    Haudenosaunee Activism 7:04
    Review & Credits 9:26

    Sources:
    https://docs.google.com/document/d/1g1BpQk_2qXtFeQBffoAT-rrogcKRaA2eNjeRCpmCrJ8/edit?usp=sharing

    Want to know more about how this series was made? Learn more here: https://docs.google.com/document/d/17yp3u28s40TdjyrJniIf4U9YA8wPtvQ1g1B-HSHQ2Q4/edit?tab=t.0#heading=h.6vtzps565m2
    ***
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    Thanks to the following patrons for their generous monthly contributions that help keep Crash Course free for everyone forever:
    oranjeez, Jason Terpstra, Chelsea S, Alan Bridgeman, Roger Harms, DexcilaDou, Krystle Young, Allison Wood, Stephen Akuffo, Katrix , Gina Mancuso, Shruti S, Martin G. Diller, Matthew Fredericksen, Brandon Thomas, Breanna Bosso, Ken Davidian, UwU, Jennifer Wiggins-Lyndall, Samantha, David Fanska, Kristina D Knight, Andrew Woods, Elizabeth LaBelle, SpaceRangerWes, Matt Curls, Quinn Harden, EllenBryn, Johnathan Williams, Leah H., Laurel Stevens, Steve Segreto, Michael Maher, Liz Wdow, Toni Miles, Perry Joyce, Evan Nelson, Katie Hoban, Mitch Gresko, Kevin Knupp, Kyle & Katherine Callahan, Tanner Hedrick, Emily Beazley, Jack Hart, Rie Ohta, Dalton Williams, Scott Harrison, Barbara Pettersen, AThirstyPhilosopher ., Thomas Sully, Bernardo Garza, Jason Rostoker, Rizwan Kassim, Indija-ka Siriwardena, Emily T, Ian Dundore, Joseph Ruf, Alex Hackman, Thomas, Constance Urist, team dorsey, Stephen McCandless, Triad Terrace, Erminio Di Lodovico, Evol Hong, Luke Sluder, Eric Koslow, Katie Dean, Tandy Ratliff, Jennifer Killen, Jason Buster, Trevin Beattie, Wai Jack Sin, Caleb Weeks, Nathan Taylor, Siobhán, Les Aker, Barrett Nuzum, John Lee, Ken Penttinen, Sarah & Nathan Catchings, Pietro Gagliardi, ClareG, Duncan W Moore IV
    __

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    15 min
  • Peripheral Nervous System: Crash Course Anatomy and Physiology #12

    It is now time to meet the system that helps your brain stay in touch with the outside world. We follow up last week's tour of the central nervous system with a look at your peripheral nervous system, its afferent and efferent divisions, how it processes information, the reflex arc, and what your brain has to say about pain.

    Pssst... we made flashcards to help you review the content in this episode! Find them on the free Crash Course App!
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    Chapters:
    Introduction: Peripheral Nervous System 00:00
    Sensory Nerve Receptors: Thermoreceptors, Photoreceptors, Chemoreceptors, Mechanoreceptors, and Nociceptors 0:56
    What is Pain? 1:54
    How Pain is Processed 2:51
    Pain Threshold vs Pain Tolerance 3:50
    How the Brain Processes Pain 4:25
    Afferent and Efferent Divisions 5:42
    Five Steps of the Reflex Arc 6:38
    What the Brain Says About Pain 8:09
    Review 9:09
    Credits 9:39

    ***

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    ***SUPPORTER THANK YOU!***

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    15 min
  • Columbus, Vasco da Gama, and Zheng He - 15th Century Mariners: Crash Course World History #21

    In which John Green teaches you about the beginning of the so-called Age of Discovery. You've probably heard of Christopher Columbus, who "discovered" America in 1492, but what about Vasco da Gama? How about Zheng He? Columbus gets a bad rap from many modern historians, but it turns out he was pretty important as far as the history of the world goes. That said, he wasn't the only pioneer plying the seas in the 1400s. In Portugal, Vasco da Gama was busy integrating Europe into the Indian Ocean Trade by sailing around Africa. Chinese admiral Zheng He was also traveling far and wide in the largest wooden ships ever built. Columbus, whether portrayed as a hero or a villain, is usually credited as the great sailor of the 15th century, but he definitely wasn't the only contender. What better way to settle this question than with a knock-down, drag-out, no holds barred, old-fashioned battle royal? We were going to make it a cage match, but welding is EXPENSIVE.

    Chapters:
    Introduction 00:00
    Notable Sailors of the 15th Century 0:39
    Zheng He, Chinese Admiral 1:23
    Reasons for China's 15th Century Naval Expeditions 2:57
    Vasco da Gama, Portuguese Explorer 4:24
    Vasco da Gama's Motivations and Strategies 5:05
    Myths about Christopher Columbus 6:33
    An Open Letter to the Line of Demarcation 7:21
    Christopher Columbus's First Voyage 8:15
    Who Was the Greatest Mariner of the 15th Century? 9:29
    Credits 10:00

    Resources:
    The Age of Reconnaissance by JH Parry - An explanation of the technologies that made these voyages possible, and a nice detailed record of many of the important voyages. https://bit.ly/3uCvKRg

    When China Ruled the Sea by Louise Levathes: A history of the Ming dynasty's ventures into maritime exploration. https://bit.ly/3jB0Rqb

    Unknown Seas by Ronald Watkins: A highly readable account of Vasco da Gama's introduction of Europe into the Indian Ocean trade. https://bit.ly/3M0QvMh

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    15 min

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