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From terpenes to steroids part 2: Squalene, cholesterol, and steroids

After learning about terpenes, lets see how are body uses them to eventually make all the steroid hormones of our body. By Ryan Patton. . Created by Ryan Scott Patton.

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  • blobby green style avatar for user jencypatel1
    Are these hormones and their structures tested in the MCAT?
    (10 votes)
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  • piceratops ultimate style avatar for user spongebob
    Doesn't steroids messes with your heart
    (0 votes)
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    • piceratops tree style avatar for user Average  Brah
      You're thinking of anabolic steroids that athletes and bodybuilders use.

      As mentioned in the videos, steroids are not just something you take to get bigger and stronger. They are hormones found in the body, such as corticosteroids (cortisol) and sex steroids (estrogen and testosterone)
      (6 votes)
  • leaf green style avatar for user LAaaca
    Why are these hydrogenes important in these examples of hormones?
    (1 vote)
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    • aqualine ultimate style avatar for user Yash Deshpande
      If you mean terpenes as a whole, they are studied under hormones because A) They make up plant hormones or phytohormones (growth regulation), as well as pheromones (attracting insects for pollination); and B) as they make up important sterols. Testosterone, progesterone, etc., are some of the most important animal hormones that are derivatives of cholesterol and other sterols.
      (3 votes)
  • blobby green style avatar for user Bri'Keia713
    how do I answer the questions, because I don't see anywhere @Mr.Odelusi
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Video transcript

Now that the light's at the end of the tunnel a little bit, I'm going to move a little bit more quickly through these reactions. So let me just copy and paste here. I'm going to clear a little bit more space. And so the body takes squalene, and through a series of ring-closing, or cyclization reactions, it makes cholesterol. And we consume some cholesterol in our diet, but our body also completes this reaction in the liver. So our body takes squalene and turns it into cholesterol in the liver. And cholesterol travels through our blood and it lives in the inside of cells and on their surfaces. In the case of endocrine organs that use steroid hormones to communicate, cholesterol can actually be altered to form the very characteristic steroid backbone. So let me draw that. So these are the four characteristic rings of the steroid backbone. As you can see, we are a really long way off, at this point, from the very beginning place that we started, which was that isoprene unit. Now that I've dragged you all the way from isoprene to the steroid backbone, I figured it was only fair that I showed you that this actually happens in your body, and there are actual steroids floating around your blood. I mentioned before that there are two important classes of steroid hormones in the body, and those are the sex hormones and the adrenal cortex steroids. With the sex hormones, I mentioned before estrogens, and we have estrasdiol and estrone. And you can see their steroid backbone. And those are predominantly made in the ovaries, and they're principally involved in secondary sex characteristics for females. And we have progesterone. It's the pregnancy hormone. It's involved in prepping the uterus, and it's also involved in maintaining a healthy pregnancy. And then we have androgens. And we have testosterone and androsterone. And similarly to the estrogens, those regulate the secondary sex characteristics, but more so in males. And they're predominantly made in the testes. Moving over to the adrenal cortex steroids, we have cortisone and cortisol. And those are the body's stress hormones, so they have a lot of the effects from anti-inflammatory to increasing carbohydrate metabolism. We also have aldosterone. Aldosterone is one of the main hormones that regulates our body's blood pressure and the fluid volume. And so I hope all these images make steroids a little bit more familiar to you, now that you've seen the classic backbone, and you know how to make it. Maybe the next time you find yourself enjoying the soothing relief of a menthol cough drop or a savory and delicious ginger snap cookie, you'll think about the countless number of terpenes that you're enjoying.