On today’s episode...CATS. Also: Hank talks about some philosophy stuff, like a few of the key concepts philosophers use when discussing belief and knowledge, such as what defines an assertion and a proposition, and that belief is a kind of propositional attitude. Hank also discusses forms of justification and the traditional definition of knowledge, which Edmund Gettier just totally messed with, using his Gettier cases.

Many thanks to Index the cat for his patience in the filming of this episode.

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Images and video via VideoBlocks or Wikimedia Commons, licensed under Creative Commons by 4.0: https://creativecommons.org/licenses/by/4.0/
“Ancient Aliens” copyright 2010 The History Channel
Classroom image via Public Domain Images http://www.public-domain-image.com/

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In which Jacob Clifford and Adriene Hill launch a brand new Crash Course on Economics! So, what is economics? Good question. It's not necessarily about money, or stock markets, or trade. It's about people and choices. What, you may ask, does that mean. We'll show you. Let's get started!

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DFTBA and keep being the exception like the Mongols.

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The majority of the universe is made up of a currently mysterious entity that pervades space: dark energy. We don’t know exactly what it is, but we do know that dark energy accelerates the expansion of space. We think this means the Universe will expand forever, even as our view of it shrinks while space expands faster all the time.

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--

GEOMETRY OF THE UNIVERSE RESOURCES
Geometry:
http://abyss.uoregon.edu/~js/c....osmo/lectures/lec15.
http://starchild.gsfc.nasa.gov..../docs/StarChild/ques

Expanding faster than light:
http://curious.astro.cornell.e....du/legal-information

General expansion:
https://en.wikipedia.org/wiki/....Metric_expansion_of_

--

Table of Contents
Majority of the Universe is Made of Dark Energy 4:35
Dark Energy Accelerates the Expansion of Space 3:42
We Think The Universe Will Expand Forever 5:20

--

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PHOTOS/VIDEOS
The Big Bang http://svs.gsfc.nasa.gov/cgi-b....in/details.cgi?aid=1 [credit: NASA]
Collision Scenario for Milky Way and Andromeda Galaxy Encounter http://www.nasa.gov/images/con....tent/654284main_i122 [credit: NASA; ESA; A. Feild and R. van der Marel, STScI]
Artist's impression of vampire star http://www.spacetelescope.org/videos/astro_bn/ [credit: ESO/M. Kornmesser]
Host Galaxies of Distant Supernovae http://www.nasa.gov/sites/defa....ult/files/images/593 [credit: NASA, ESA, and A. Riess (STScl)]
Dark Energy Expands the Universe http://svs.gsfc.nasa.gov/cgi-b....in/details.cgi?aid=1 [credit: NASA]
Expanding Universe http://www.spacetelescope.org/....videos/hst15_expandi [credit: ESA/Hubble (M. Kornmesser & L. L. Christensen)]
Hubble Ultra Deep Field 2014 http://hubblesite.org/newscent....er/archive/releases/ [credit: NASA, ESA, H. Teplitz and M. Rafelski (IPAC/Caltech), A. Koekemoer (STScI), R. Windhorst (Arizona State University), and Z. Levay (STScI)]

In which John Green teaches you about Imperialism. In the late 19th century, the great powers of Europe were running around the world obtaining colonial possessions, especially in Africa and Asia. The United States, which as a young country was especially suceptible to peer pressure, followed along and snapped up some colonies of its own. The US saw that Spain's hold on its empire was weak, and like some kind of expansionist predator, it jumped into the Cuban War for Independence and turned it into the Spanish-Cuban-Phillipino-American War, which usually just gets called the Spanish-American War. John will tell you how America turned this war into colonial possessions like Puerto Rico, The Philippines, and almost even got to keep Cuba. The US was busy in the Pacific as well, wresting control of Hawaii from the Hawaiians. All this and more in a globe-trotting, oppressing episode of Crash Course US History.

Our Subbable Dooblydoo message today is from James Williams. He writes, "Gracie Mckenna, luck is, indeed, for suckers."

You can support Crash Course directly by subscribing and pledging a monthly gift at https://www.patreon.com/crashcourse. You could even have your own message in the Dooblydoo. If you subscribed via Subbable when the service first launched, you may need to go back and resubscribe. Thanks for your support.

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. As America transitioned from the 19th to the 20th century, she experimented with imperialism through war and annexation; one of the most lasting effects of this time was the annexation of Hawaii, America's 50th state: https://www.commonlit.org/text....s/the-1897-petition-
America’s imperial aims continued for decades, particularly with the Monroe Doctrine: https://www.commonlit.org/text....s/the-monroe-doctrin

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In which John Green teaches you about the Vereenigde Oostindische Compagnie, doing business as the VOC, also known as the Dutch East India Company. In the 16th and 17th centuries, the Dutch managed to dominate world trade, and they did all through the pioneering use of corporations and finance. Well, they did also use some traditional methods like violently enforced monopolies, unfair trade agreements, and plain old warfare. You'll learn how the Dutch invented stuff like joint stock corporations, maritime insurance, and futures trading. Basically, how the Dutch East India Company crashed the US economy in 2008. I'm kidding. Or am I?

Citation 1: William J. Bernstein, A Splendid Exchange: How Trade Shaped the World. Grove Press. 2008. p. 218
Citation 2: Stephen R. Bown. Merchant Kings: When Companies Ruled the World, 1600-1900. New York. St. Martin’s Press. 2009. p. 28
Citation 3: Bernstein p. 223
Citation 4: Bernstein p. 228
Citation 5: Bown p. 53

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Go to https://subbable.com and click the "continue to patreon button." You will be guided through the process to merge your account with Patreon to continue supporting your portfolio of creators. Make sure to use the money in your perk bank by August 1st, 2015. Get yourself something nice you deserve it! Also. you are the best. Yes. You. You are awesome, and we can't thank you enough!

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Today Phil explains that YES, there are other planets out there and astonomers have a lot of methods for detecting them. Nearly 2000 have been found so far. The most successful method is using transits, where a planet physically passes in front of its parent star, producing a measurable dip in the star’s light. Another is to measuring the Doppler shift in a star’s light due to reflexive motion as the planet orbits. Exoplanets appear to orbit nearly every kind of star, and we’ve even found planets that are the same size as Earth. We think there may be many billions of Earth-like planets in our galaxy.

This is a reupload of last week's episode to correct an error in the way we covered reflexive motion.
For more information on the change and reflexive motion, you can check out Phil's blog: http://www.slate.com/blogs/bad...._astronomy/2015/08/0
--

Table of Contents
Other Planets Orbit Other Stars 2:10
Nearly 2000 Have Been Found 9:29
Transits 5:44
Doppler Shift 3:30
Exoplanets Orbit Nearly Every Kind of Star 8:44
Billions of Earth-Like Planets 9:33

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PHOTOS/VIDEOS
Stars as viewed from ISS https://www.youtube.com/watch?v=TOQrx-7qgak [credit: Alex Rivest & NASA]
Jupiter http://www.nasa.gov/centers/go....ddard/multimedia/lar [credit: NASA]
Mars http://mars.jpl.nasa.gov/multi....media/images/?ImageI [credit: NASA/JPL-Caltech/MSSS]
Mercury http://solarsystem.nasa.gov/multimedia/display.cfm?Category=Planets&IM_ID=7543 [credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington]
Earth https://www.nasa.gov/topics/ea....rth/overview/index.h [credit: NASA]
Uranus http://photojournal.jpl.nasa.gov/catalog/PIA18182 [credit: NASA/JPL-Caltech]
Lost in the Glare http://planetquest.jpl.nasa.gov/video/23 [credit: NASA Kepler Mission/Dana Berry]
Reflexive Motion gifs http://spaceplace.nasa.gov/barycenter/en/ [credit: NASA]
Artist's conception of PSR B1257+12's system of planets https://en.wikipedia.org/wiki/....Pulsar_planet#/media [credit: NASA/JPL-Caltech/R. Hurt (SSC)]
Artist’s impression of the exoplanet 51 Pegasi b (image) http://www.eso.org/public/usa/images/eso1517a/ [credit: ESO/M. Kornmesser/Nick Risinger (skysurvey.org)]
Artist’s impression of the exoplanet 51 Pegasi b (video) http://www.eso.org/public/usa/videos/eso1517b/ [credit: ESO/M. Kornmesser/Nick Risinger (skysurvey.org)]
Kepler Transit Graph http://planetquest.jpl.nasa.gov/video/22 [credit NASA Kepler Mission/Dana Berry]
Kepler “Beauty Shot” http://planetquest.jpl.nasa.gov/video/2 [credit: NASA/Kepler mission/Dana Berry]
The Brown Dwarf 2M1207 and its Planetary Companion https://www.eso.org/public/usa/images/eso0515a/ [credit: ESO]
Beta Pictoris b http://www.eso.org/public/arch....ives/images/screen/e [credit: ESO]
A size comparison of the planets in the Kepler-37 system and objects in the Solar System http://photojournal.jpl.nasa.gov/catalog/PIA16694 [credit: NASA/Ames/JPL-Caltech]
Water World http://planetquest.jpl.nasa.gov/video/39 [credit: NASA Kepler Mission/Dana Berry]
Earth-like World http://planetquest.jpl.nasa.gov/video/42 [credit: NASA Kepler Mission/Dana Berry]

You can directly support Crash Course at https://www.patreon.com/crashcourse Subscribe for as little as $0 to keep up with everything we're doing. Free is nice, but if you can afford to pay a little every month, it really helps us to continue producing this content.

In which John Green teaches you about American involvement in World War I, which at the time was called the Great War. They didn't know there was going to be a second one, though they probably should have guessed, 'cause this one didn't wrap up very neatly. So, the United States stayed out of World War I at first, because Americans were in an isolationist mood in the early 20th century. That didn't last though, as the affronts piled up and drew the US into the war. Spoiler alert: the Lusitania was sunk two years before we joined the war, so that wasn't the sole cause for our jumping in. It was part of it though, as was the Zimmerman telegram, unrestricted submarine warfare, and our affinity for the Brits. You'll learn the war's effects on the home front, some of Woodrow Wilson's XIV Points, and just how the war ended up expanding the power of the government in Americans' lives.

Subbable message!!!: Jared Richardson says, "All true love is beautiful. Support your LGBT community."

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 complex secret alliances of Europe led to World War I: https://www.commonlit.org/text....s/a-mad-dash-to-disa
It took several years before Americans joined the war: https://www.commonlit.org/text....s/to-the-front-lines
After the war, President Woodrow Wilson wanted to prevent a future World War, and promoted creating a League of Nations, established following the Treaty of Versailles: https://www.commonlit.org/text....s/the-treaty-of-vers

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•••SUBBABLE MESSAGE•••

TO : Phoebe and James McMullan
FROM : Dad

Continue being awesome Phoebe & James from John & Hank!

***

You can directly support Crash Course at http://www.subbable.com/crashcourse Subscribe for as little as $0 to keep up with everything we're doing. Also, if you can afford to pay a little every month, it really helps us to continue producing great content.

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Today on Crash Course Anatomy & Physiology, Hank breaks down the parts and functions of one of your body's unsung heroes: your epithelial tissue.

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Table of Contents:

Epithelial Tissue Creates Inner & Outer Boundaries 2:19.3
Layering: Simple or Stratefied 5:26
Shape: Squamous, Cuboidal, or Columnar 3:34.5
Epithelial Cells Are Polar 7:17.4
Apical & Basal Sides 7:22
Selectively Permeable 7:43
Glandular Epithelial Tissue Forms Endocrine & Exocrine Glands 8:20.3

--

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Hank resists the urge to devour a slice of pizza so that he can walk you through the way we experience our major special senses. It all boils down to one thing: sensory cells translating chemical, electromagnetic, and mechanical stimuli into action potentials that our nervous system can make sense of. Today we're focusing on smell (olfaction) and taste (gustation), which are chemical senses that call on chemoreceptors. As usual, we'll begin with a quick look at how these things can go wrong.

Table of Contents
Anatomy and Physiology of Smell 2:26
The Olfactory Sensory Neurons 3:01
Receptors → Glomerulus → Mitral Cells → Brain 3:47
Taste Receptor Epithelial Cells 7:30
Receptors Trigger Action Potentials to Four Different Cranial Nerves 8:26


***

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In this episode of Crash Course Anatomy & Physiology, Hank gives you a brief history of histology and introduces you to the different types and functions of your body's tissues.

--

Table of Contents:

Nervous, Muscle, Epithelial & Connective Tissues 1:23
History of Histology 2:07
Nervous Tissue Forms the Nervous System 5:17
Muscle Tissue Facilitates All Your Movements 7:00
Identifying Samples 9:03

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In which Adriene Hill and Jacob Clifford teach you about specialization and trade, and how countries decide whether they're going to make stuff or trade for stuff. You'll learn about things like comparative advantage, the production possibilities frontier and how to make pizza!

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

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FROM: Anthony M.

"Making our own history awesome! Happy 3 year Anniversary!"

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"The earth is but one country, and mankind its citizens."

Thank you so much to all of our awesome supporters for their contributions to help make Crash Course possible and freely available for everyone forever:

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We’ve covered a lot of incredible stuff, but this week we’re talking about the weirdest objects in space: BLACK HOLES. Stellar mass black holes form when a very massive star dies, and its core collapses. The core has to be more than about 2.8 times the Sun’s mass to form a black hole. Black holes come in different sizes, but for all of them, the escape velocity is greater than the speed of light, so nothing can escape, not matter or light. They don’t wander the Universe gobbling everything down around them; their gravity is only really intense very close to them. Tides near a stellar mass black hole will spaghettify you, and time slows down when you get near a black hole — not that this helps much if you’re falling in.

Crash Course Astronomy Poster: http://store.dftba.com/product....s/crashcourse-astron

--

Table of Contents
How Stellar Mass Black Holes Are Formed 1:03
The Core 1:43
Nothing Can Escape Once It’s Inside 2:29
Gravity Intensifies The Closer You Get 3:33
Spaghettification 6:01
Time Will Slow Down Near A Black Hole 8:01

--

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--

PHOTOS/VIDEOS
White Dwarf Pulses Like a Pulsar http://www.nasa.gov/centers/go....ddard/news/topstory/ [credit: NASA, Casey Reed]
Swift Reveals New Phenomenon in a Neutron Star http://www.nasa.gov/mission_pa....ges/swift/bursts/new [credit: NASA's Goddard Space Flight Center]
Black Holes - Monsters in Space https://en.wikipedia.org/wiki/....File:Black_Holes_-_M [credit: NASA/JPL-Caltech, Wikimedia Commons]
What if the Sun became a black hole? (artist's impression) http://www.spacetelescope.org/....videos/hubblecast43g [credit: ESA/Hubble (M. Kornmesser)]
Black Hole Animation http://chandra.harvard.edu/pho....to/2003/0203long/ani [credit: NASA/SAO/CXC/D.Berry]
Star Destroyer http://svs.gsfc.nasa.gov/cgi-b....in/details.cgi?aid=1 [credit: Space Telescope Science Institute (STScI) and NASA's Goddard Space Flight Center]
Black hole deforms space http://www.spacetelescope.org/....videos/hst15_blackho [credit: ESA/Hubble (M. Kornmesser & L. L. Christensen)]
Black hole close-up (artist's impression) http://www.spacetelescope.org/videos/heic0211c/ [credit: European Space Agency, NASA and Felix Mirabel (the French Atomic Energy Commission & the Institute for Astronomy and Space Physics/Conicet of Argentina)]

Want more videos about psychology every Monday and Thursday? Check out our sister channel SciShow Psych at https://www.youtube.com/scishowpsych!

Feeling motivated? Even if you are, do you know why? The story of Aaron Ralston can tell us a lot about motivation. In this episode of Crash Course Psychology, Hank tells us Ralston's story, as well as 4 theories of motivation and some evolutionary perspectives on motivation.

--
Table of Contents

Four Theories of Motivation:
Evolutionary Perspective 1:38:22
Drive-Reduction 2:45:10
Optimal Arousal 3:38:21
Maslow's Hierarchy of Needs 4:49:04
How Sex, Hunger, and the Need to Belong Motivate us 5:29:02

--
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Massive stars fuse heavier elements in their cores than lower mass stars. This leads to the creation of heavier elements up to iron. Iron robs critical energy from the core, causing it to collapse. The shock wave, together with a huge swarm of neutrinos, blast through the star’s outer layers, causing it to explode. The resulting supernova creates even more heavy elements, scattering them through space. Also, happily, we’re in no danger from a nearby supernova.

Crash Course Astronomy Poster: http://store.dftba.com/product....s/crashcourse-astron

--

Table of Contents
Massive Stars Fuse Heavier Elements Up To Iron 1:15
Iron Uses High Amounts of Energy, Thus Making Stars Collapse 3:58
The Resulting Supernova Creates Even Heavier Elements 10:00
Relax, Something Else Will Kill You 9:04

--

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--

PHOTOS/VIDEOS
Blowing Bubbles http://chandra.harvard.edu/res....ources/animations/pn [credit: NASA/CXC/April Jubett]
The Sizes of Stars http://www.eso.org/public/images/eso1030c/ [credit: ESO/M. Kornmesser]
Red giants https://commons.wikimedia.org/....wiki/File:Redgiants. [credit: Wikimedia Commons]
Alpha Orionis http://imgsrc.hubblesite.org/h....u/db/images/hs-1996- [credit: A. Dupree (CfA), NASA, ESA]
Sun and VY Canis Majoris https://commons.wikimedia.org/....wiki/File:Sun_and_VY [credit: Wikimedia Commons]
Witch Head Nebula and Rigel http://www.deepskycolors.com/a....rchive/2009/11/16/wi [credit: Rogelio Bernal Andreo]
Layers of a massive star https://en.wikipedia.org/wiki/....User:FT2/scc#/media/ [credit: Wikimedia Commons]
NASA's Swift Reveals New Phenomenon in a Neutron Star http://www.nasa.gov/mission_pa....ges/swift/bursts/new [credit: NASA's Goddard Space Flight Center]
What is a black hole? http://www.nasa.gov/audience/f....orstudents/k-4/stori [credit: NASA/CXC/M.Weiss]
The Death of Stars http://www.spacetelescope.org/....videos/hubblecast52a [credit: ESA/Hubble]
Giant Mosaic of the Crab Nebula http://www.nasa.gov/multimedia..../imagegallery/image_ [credit: NASA, ESA, J. Hester (Arizona State University)]
Hubble and Chandra spot a celestial bauble http://www.spacetelescope.org/images/heic1018b/ [credit: NASA, ESA, the Hubble Heritage Team (STScI/AURA), and NASA/CXC/SAO/J. Hughes]
Vela Supernova Remnant http://www.glitteringlights.co....m/Images/Nebulae/i-p [credit: Marco Lorenzi]
Spica [credit: Phil Plait]
Cassiopeia A https://en.wikipedia.org/wiki/....Cassiopeia_A#/media/ [credit: Oliver Krause (Steward Observatory) George H. Rieke (Steward Observatory) Stephan M. Birkmann (Max-Planck-Institut fur Astronomie) Emeric Le Floc'h (Steward Observatory) Karl D. Gordon (Steward Observatory) Eiichi Egami (Steward Observatory) John Bieging (Steward Observatory) John P. Hughes (Rutgers University) Erick Young (Steward Observatory) Joannah L. Hinz (Steward Observatory) Sascha P. Quanz (Max-Planck-Institut fur Astronomie) Dean C. Hines (Space Science Institute)]
Sloshing Supernova http://svs.gsfc.nasa.gov/cgi-b....in/details.cgi?aid=1 [credit: NASA's Goddard Space Flight Center Video and images courtesy of NASA/JPL-Caltech]
Star Burst http://svs.gsfc.nasa.gov/cgi-b....in/details.cgi?aid=1 [credit: NASA's Goddard Space Flight Center Video courtesy of ESA/Hubble/L. Calcada]

Life is chaos and the universe tends toward disorder. But why? If you think about it, there are only a few ways for things to be arranged in an organized manner, but there are nearly infinite other ways for those same things to be arranged. Simple rules of probability dictate that it's much more likely for stuff to be in one of the many disorganized states than in one of the few organized states. This tendency is so unavoidable that it's known as the 2nd Law of Thermodynamics. Obviously, disorder is a pretty big deal in the universe and that makes it a pretty big deal in chemistry - it's such a big deal that scientists have a special name for it: entropy. In chemistry, entropy is the measure of molecular randomness, or disorder. For the next thirteen minutes, Hank hopes you will embrace the chaos as he teaches you about entropy.

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Table of Contents
Second Law of Thermodynamics :45
Entropy 2:01
DEMONSTRATION! 4:28
BA(OH)2•8H2O+NH4Ci 10:25
J.W. Gibbs & Gibbs Free Energy 7:23


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In which John Green teaches you about the Little Ice Age. The Little Ice Age was a period of global cooling that occurred from the 13th to the 19th centuries. This cooling was likely caused by a number of factors, including unusual solar activity and volcanic eruptions. The Little Ice Age greatly impacted human social orders, especially during the 17th century. When the climate changed, and weather became unpredictable, the world changed profoundly. Poor harvests led to hunger, which led to even less productivity, which even resulted in violent upheaval in a lot of places. All this from a little change in the temperature? Definitely.

You can directly support Crash Course at https://www.patreon.com/crashcourse Subscribe for as little as $0 to keep up with everything we're doing. Free is nice, but if you can afford to pay a little every month, it really helps us to continue producing this content.

Read more about The Little Ice Age here: http://www.amazon.com/Global-C....risis-Climate-Catast

Today Phil explains how telescopes work and offers up some astronomical shopping advice.

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How Telescopes Work 1:07
Refractors vs Reflectors 2:50
Technology and the Light Spectrum 7:45

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PBS Digital Studios: http://youtube.com/pbsdigitalstudios

Follow Phil on Twitter: https://twitter.com/badastronomer

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PHOTOS/VIDEOS
http://en.wikipedia.org/wiki/G....alileo_Galilei#media
http://en.wikipedia.org/wiki/H....uman_eye#mediaviewer
http://en.wikipedia.org/wiki/R....efracting_telescope#
http://commons.wikimedia.org/w....iki/File:Positive_le
http://www.eso.org/public/imag....es/yb_vlt_moon_cnn_c
http://en.wikipedia.org/wiki/J....upiter#mediaviewer/F
http://en.wikipedia.org/wiki/W....ide_Field_and_Planet
http://commons.wikimedia.org/w....iki/File:Prime_focus
http://commons.wikimedia.org/w....iki/File:Inspection_
https://www.youtube.com/watch?....v=ui6ernRFxOg#t=2m22
http://en.wikipedia.org/wiki/W....illiam_Herschel#medi
http://commons.wikimedia.org/w....iki/File:Grand_Canyo
http://commons.wikimedia.org/w....iki/File_talk:EM_spe
https://www.youtube.com/watch?....v=RqX9vLj3_7w#t=4m52
http://pprc.qmul.ac.uk/~still/....wordpress/?page_id=1
http://en.wikipedia.org/wiki/V....ERITAS#mediaviewer/F
http://en.wikipedia.org/wiki/A....strophotography#medi
http://en.wikipedia.org/wiki/A....strophotography#medi
http://en.wikipedia.org/wiki/F....ile:PIA18593-Mars-Co
http://en.wikipedia.org/wiki/F....ile:NASA-HS201427a-H
http://upload.wikimedia.org/wi....kipedia/commons/2/2b
http://upload.wikimedia.org/wi....kipedia/commons/thum
http://upload.wikimedia.org/wi....kipedia/commons/5/56
http://hubblesite.org/newscent....er/archive/releases/

As we wrap up Crash Course Philosophy, we’re using the things we’ve learned to explore big issues like the value of life. Today, we’re discussing abortions in cases of fetal abnormality, assisted suicide, and euthanasia. We will consider the standard of substituted judgment and the values people hold on both sides of these issues—values about the sacredness of life, and the importance of a life of quality, as well as the values of personal liberty and avoiding pain.

Want more Crash Course in person? We'll be at NerdCon: Nerdfighteria in Boston on February 25th and 26th! For more information, go to http://www.nerdconnerdfighteria.com/

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The Latest from PBS Digital Studios: https://www.youtube.com/playli....st?list=PL1mtdjDVOoO

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Produced in collaboration with PBS Digital Studios: http://youtube.com/pbsdigitalstudios

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In which John Green ACTUALLY teaches about the Civil War. In part one of our two part look at the US Civil War, John looks into the causes of the war, and the motivations of the individuals who went to war. The overarching causes and the individual motivations were not always the same, you see. John also looks into why the North won, and whether that outcome was inevitable. The North's industrial and population advantages are examined, as are the problems of the Confederacy, including its need to build a nation at the same time it was fighting a war. As usual, John doesn't get much into the actual battle by battle breakdown. He does talk a little about the overarching strategy that won the war, and Grant's plan to just overwhelm the South with numbers. Grant took a lot of losses in the latter days of the war, but in the end, it did lead to the surrender of the South. If you want to learn more about the Civil War, we recommend these books:
Battle Cry of Freedom by James McPherson
The Civil War by Shelby Foote

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. There were many causes of the American Civil War and events that led to disunion: https://www.commonlit.org/text....s/causes-of-the-amer
Once the war started, its outcome was determined by the different abilities and resources of the divided North and South: https://www.commonlit.org/text....s/a-nation-divided-n

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Hank takes us on the fascinating journey through our excretory system to learn how our kidneys make pee.

Crash Course Biology is now available on DVD! http://dft.ba/-8bCC

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References
http://www.emc.maricopa.edu/fa....culty/farabee/biobk/
http://www.khanacademy.org/sci....ence/biology/v/the-k
Campbell Biology, 9th ed.

Table of Contents
1) Homeostasis & Osmoregulation 00:00
2) Urea & Uric Acid 01:30
3) Kidneys 02:49
4) Nephron 03:40
5) Glomerulus 4:15
6) Bowman's Capsule 04:25
7) Proximal Convoluted Tubule 04:49
8) Biolography 06:16
9) Loop of Henle 07:36
10) Distal Convoluted Tubule 09:23
11) Collecting Ducts 09:57
12) Ureters, Bladder & Urethra 10:45

crashcourse, crash course, biology, science, human, anatomy, physiology, homeostasis, organ, urine, urinary, kidney, ureter, bladder, urethra, osmoregulation, balance, metabolism, ammonia, urea, uric acid, toxicity, blood, nephron, renal artery, glomerulus, bowman's capsule, filtrate, loop of henle, renal cortex, renal medulla, freidrich henle, diuretic, anti-diuretic hormone, kangaroo rat, beaver, pee, osmosis Support CrashCourse on Subbable: http://subbable.com/crashcourse