Metabolism is a complex process that has a lot more going on than personal trainers and commercials might have you believe. Today we are exploring some of its key parts, including vital nutrients — such as water, vitamins, minerals, carbs, fats, and proteins — as well as how anabolic reactions build structures and require energy, while catabolic reactions tear things apart and release energy.

Anatomy of Hank Poster:

Table of Contents
Water, Vitamins, Minerals, Carbs, Fats and Proteins 3:47
Anabolic Reactions Build Structures and Require Energy 2:59
Catabolic Reactions Tear Things Apart and Release Energy 3:17
Metabolism 2:30


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  1. You guys are doing an amazing job. I wish your videos could reach every
    child, teenager or adult who wants to learn. Congratulations!

  2. I love these videos . I understand everything your saying too . My family
    though are like what the hell are you watching ?

  3. I wonder how you guys will be able to do the male and female reproductive
    systems seeing that YouTube requires censoring? Or is censoring not
    required since it is for educational purposes?

  4. Honestly, I don’t understand why he has to talk that fast?! I mean it’s
    neither cool or useful for us. Why the hack can’t he talk in a rythym where
    everybody understands him, also non-native English speakers.

  5. I weigh NO kilograms. I weigh some pounds though 🙂
    I understand the need to appear cool and smart but, would it be possible to
    add imperial numbers as a pop-up within your videos so us dumb Americans
    can more easily follow along?

    Attention metric police, I have a calculator, yes and use both systems. Not
    interested in hearing about the wonders of the metric system and how
    superior it is to imperial. Thanks!

    • +Cristina D A tad harsh there, Ms D. Where I live is what pays for this
      video and the public TV network they partner with. I’m not asking him to
      change his coolness. All I’m asking is for a small parenthesis on the
      screen where imperial numbers are shown. That would instantly relate to an
      additional 300 million people.

    • +JoeyRodz74 I don’t know how they teach where you live, but science in done
      in IS (SI) worldwide to avoid discrepancies. He’s not being smart or cool,
      he’s using the standard of the field. So don’t ask stupid favors. Suck it

    • +JoeyRodz74 I’m a bisystemal(?), I weight myself in lb, but my food is in
      g, I’m 6 foot tall, but my job is 6km from home, I’m 37°C but my pool is
      70°F, I drink 12oz beer, but I buy 4L of milk, I make calculation of force
      in Newton, but my tools are in PSI. I put 50L of gaz in my car but 2 gallon
      in my mower… I will buy 50” of that fabric but on the receipt it will be
      1270mm… Metric is more simple when doing math and shit but I dont know
      why, I will use imperial if I’m building anything… I think crashcourse is
      trying to convert the follower of the imperial system to the metric ;). For
      me, I believe in both system…. And I’m talking for no good reason
      again… time to go to sleep

  6. Yes!!! We need more of this in fitness and health and less “bro science”.
    Really enjoyed it. We have videos on physiology and health too!

  7. When you say that a your body will not think of making a protein if all the
    constituent amino acids are present. I found listening to Giulia Enders
    book “gut” that the process is terminated and the proteins discarded or
    reused by the body. I found this fact just today and seems contradictory. I

  8. Wow I literally have a test on this tomorrow and was planing on
    procrastinating when i saw it and didn’t realize what it was bout till
    after I watched it.

  9. Learned more in 10 minutes than in my entire 3 years of high school! Keep
    up the good work guys! Love all of you from CrashCourse!

  10. So, you are secondly most made of protein but you don’t necessarily need to
    eat protein to have protein because all living foods are made of protein,
    right? If my diet mainly consists of fruits and vegetables I am basically
    getting most of my protein as long as I eat enough calories?

  11. Good video as always, but clearly carbohydrates do not provide all our
    energy. It is used for high intensity activity and the brain uses it for
    its function. But talk to professional athletes and they will tell you how
    fats make up the vast majority of their fuel source. It burns long and

    • +Jacob D Wunsch Professional athletes are not a reference to go by for the
      common folk. Their metabolism is constantly running on overclock, which is
      why they need to consume extra amounts of fats that contain twice the
      potential energy of carbs and proteins. This overclocking can actually burn
      out your body in the long run and many athletes will literally age more
      quickly than the average human because they are pushing the limits of their
      metabolism ALL THE TIME. Our bodies aren’t infinitely renewable.
      Carbohydrates remain the primary energy source for almost everyone. So lay
      off the fatty foods mmmmkay?

  12. So it understood we need Omega 3 & 6 fatty acids because our body can’t
    product it naturally. BUT I’ve learnt through reading Grain Brain 3 is much
    better for brain and body function were 6 fatty acids can cause
    inflammation and a lot of harm. Does anyone have any studies or evidence to
    support or refute that claim. I trust David Perlmutter the author very much
    he’s well respected. But still want more evidence.

  13. Mr hank if possible can you start a physics section. I think your videos
    are very good and your videos on physics would be great

  14. at 3:29, Hank talks about how breaking the bonds releases energy, but I
    thought that forming bonds release energy, and breaking bonds actually
    consumes energy? By that logic, anabolic reactions would actually release

  15. brain functions very well on keytones,.. you didnt get into keytones, vs
    carbs as far as metabolism,.. very important in dealing with metabolic
    dysfunctions,. liver makes all the glucose the body needs with out eating
    carbs, there are no essential carbs. but there are essential fats and
    proteins (see Volek and Phinney for research)

  16. Humans survived for 200,000 years without adequate access to carbohydrates.
    Fat is what our bodies evolved to use for energy. NOT CARBS. The theory
    that we need carbs for energy is the main reason the world is developing an
    obesity problem. I still love crash course though.

  17. Hank, I love your shows. Please mention how the body without Glucose can
    make ketones in the liver. And that actually many of the bodies functions
    prefer using certain ketones to glucose and how it is arguably the over
    indulgence of glucose which could be the cause of many modern diseases.

  18. Me: 30% water, 1% fat (I am literally anorexic), 10% protein, 0.5% carbs,
    1% mineral, 20% darkness and evil, 37.5% void of nothingness

    • +LiwenDiamond 1. I am not attention seeking 2. It was a joke 3. You might
      have fed the troll, even though I don’t intent to be spamming how ironic

    • +Skarmx2 You forgot 200% emo kid attention seeker, which is how you got
      that very reply you’re reading.

      Oh shit I just fed the troll didn’t?

  19. Loving this new bit of having little animations interacting with you on
    screen, Loved little Sisyphus pushing the bolder up your arm and on the
    recent CC Astronomy it really cracked me up when Phil became Spectroscopy

  20. There’s Hydrogen and Helium
    Then Lithium, Beryllium
    Boron, Carbon everywhere
    Nitrogen all through the air

    With Oxygen so you can breathe
    And Fluorine for your pretty teeth
    Neon to light up the signs
    Sodium for salty times

    Magnesium, Aluminium, Silicon
    Phosphorus, then Sulfur, Chlorine and Argon
    Potassium, and Calcium so you’ll grow strong
    Scandium, Titanium, Vanadium and Chromium and Manganese

    This is the Periodic Table
    Noble gas is stable
    Halogens and Alkali react aggressively
    Each period will see new outer shells
    While electrons are added moving to the right

    Iron is the 26th
    Then Cobalt, Nickel coins you get
    Copper, Zinc and Gallium
    Germanium and Arsenic

    Selenium and Bromine film
    While Krypton helps light up your room
    Rubidium and Strontium then Yttrium, Zirconium

    Niobium, Molybdenum, Technetium
    Ruthenium, Rhodium, Palladium
    Silver-ware then Cadmium and Indium
    Tin-cans, Antimony then Tellurium and Iodine and Xenon and then Caesium

    Barium is 56 and this is where the table splits
    Where Lanthanides have just begun
    Lanthanum, Cerium and Praseodymium

    Neodymium’s next too
    Promethium, then 62’s
    Samarium, Europium, Gadolinium and Terbium
    Dysprosium, Holmium, Erbium, Thulium
    Ytterbium, Lutetium

    Hafnium, Tantalum, Tungsten then we’re on to
    Rhenium, Osmium and Iridium
    Platinum, Gold to make you rich till you grow old
    Mercury to tell you when it’s really cold

    Thallium and Lead then Bismuth for your tummy
    Polonium, Astatine would not be yummy
    Radon, Francium will last a little time
    Radium then Actinides at 89

    This is the Periodic Table
    Noble gas is stable
    Halogens and Alkali react aggressively
    Each period will see new outer shells
    While electrons are added moving to the right

    Actinium, Thorium, Protactinium
    Uranium, Neptunium, Plutonium
    Americium, Curium, Berkelium
    Californium, Einsteinium, Fermium
    Mendelevium, Nobelium, Lawrencium
    Rutherfordium, Dubnium, Seaborgium
    Bohrium, Hassium then Meitnerium
    Darmstadtium, Roentgenium, Copernicium

    Ununtrium, Flerovium
    Ununpentium, Livermorium
    Ununseptium, Ununoctium
    And then we’re done!

    Don’t ask why…
    Just felt like it

  21. Dear Muricans,
    Wearing dressshirt over tshirt is as same as wering 2 coats or two pair of
    pants. Unbuttoned as casual look only.
    Regards Europe.

  22. Thank You so much for your videos Hank. I had no idea you were already 35.
    Have you ever considered doing videos on ochem? Have a great week.

  23. Great lesson! I love a good refresher on nutrition as it is what I’m going
    to school for. Loved the Gordon Ramsay animation, by the way!

  24. I learned in Chemistry that forming bonds releases energy and breaking
    bonds takes energy. Why is this seemingly reversed in anabolism (forming
    bonds but taking energy) and catabolism? (breaking bonds but releasing
    energy) Help!

  25. I love you crash course! I aced my microbiology, anatomy and physiology,
    and biology classes all cause of watching your videos of repeat. Thank you.
    Thank you so much.


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