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Autonomic vs somatic nervous system

Understand the different divisions of the brain that control our muscles.  By Raja Narayan. Created by Raja Narayan.

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  • orange juice squid orange style avatar for user Abraham George
    What is the difference between the neurotransmitters epinephrine and norepinephrine?
    (9 votes)
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    • aqualine ultimate style avatar for user GenoC
      Norepinephrine is also most commonly found to be a neurotransmitter directly effecting the target, while epinephrine released by the adrenal medulla is a neuroendocrine and travels throughout the body in the blood/plasma.
      (13 votes)
  • orange juice squid orange style avatar for user Paul Norwood
    So, is that the difference between adrenaline and noradrenaline, that one is the hormone and the other the neurotransmitter? I just don't get what makes them different.
    (4 votes)
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    • piceratops seed style avatar for user kenzie
      Really, there is minimal difference. The primary difference lies in the receptors that they have a higher affinity for. Noradrenaline (NE) prefers alpha and beta 1 receptors while adrenaline (E) has greater specificity for only alpha receptors.
      Binding to alpha receptors causes a constriction of the vessel walls; binding to beta-1 receptors causes increased force and speed of cardiac contractions, increased irritability of the heart, &c.; and binding to beta-2 receptors causes bronchodilatation and vasodilation in the walls of the blood vessels of muscles.

      Sorry for the late response and it is really basic as I don't know how much biochemistry you know.
      (11 votes)
  • blobby green style avatar for user Trav.F32
    At the end of this video you said that these were the parts of the CNS. I thought they were part of the PNS. Isn't the CNS just basically consist of the brain and spinal cord?
    (6 votes)
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    • leaf blue style avatar for user eira
      This is the correction pop-up that "Wrath of Academy" mentioned:
      Raja said, "two major divisions of the central nervous system", but meant "two major divisions of the peripheral nervous system".

      Before that, there was this correction pop-up:
      Raja said "the sympathetic nervous system use NE", but meant "the pre-ganglionic nerves of the sympathetic nervous system use ACh and the post-ganglionic nerves use NE."

      ...and neither did show when watched in full-screen.
      (3 votes)
  • piceratops seed style avatar for user joseb918
    if a person don't have a proper alignment of the spinal cord. That person could have problem with the autonomic nervous system?
    (4 votes)
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  • leafers ultimate style avatar for user Youngmin Kim
    Is autonomic = involuntary and somatic = voluntary?
    (3 votes)
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  • duskpin seedling style avatar for user zion1190032
    What's the difference between somatic and autonomic?
    Are you saying that autonomic is involuntary or somatic is voluntary?
    (2 votes)
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    • leaf green style avatar for user Joanne
      Somatic Nervous System is the one that allows conscious (voluntary) control of skeletal muscles. Autonomic N. S. has the unconscious (involuntary) control of the body and it has 2 branches, the Sympathetic and Parasympathetic NS. You are going to need book, I suggest OpenStax Anatomy and Physiology textbooks, because they are free and available on line at https://openstax.org/details/books/anatomy-and-physiology
      Also you can go to Wikipedia, and look them up there. I would use the book, and then use Wikipedia for more detail.
      (2 votes)
  • starky ultimate style avatar for user Mr.Christian
    what about the sensory nervous system?
    (2 votes)
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  • orange juice squid orange style avatar for user junemcat
    at , which neurotransmitter is for sym and which is for para? there's something about pre and post? confused.
    (1 vote)
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    • leafers ultimate style avatar for user William H
      The same neurotransmitters can be found in both the sympathetic and parasympathetic nervous systems although the concentration may be more. For pre and post I think you refer to pre and post synaptic. Pre is the starting neuron, post is the one that receives the signal.
      (3 votes)
  • blobby green style avatar for user lubnashaikh04
    In medical shows, why do the doctors ask for "epi" when someone's heart is stopping if epi as in epinephrine is the part of parasympathetic nervous system? wouldn't it slow down heart ?
    (1 vote)
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  • blobby green style avatar for user Tania Bardsley
    Did you mean that these are the two components of the PERIPHERAL nervous system, instead of the CENTRAL nervous system? I thought the CNS was made up of the brain and spinal cord.
    (1 vote)
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Video transcript

We can think of the nervous system as split up into two other parts. There's going to be an autonomic nervous system branch. And as the name kind of sounds like, this is your automatic control. That's the involuntary parts that we talked about from above. Beside that, there's also going to be a control that we exert. And so that's going to be called the somatic nervous system. So that's something that we control, somatic nervous system. Underneath the autonomic classification, you can break this up into two other parts. One is called the sympathetic nervous system. And we sort of alluded to that above when we were talking about the sympathetic ganglia that were part of involuntary control. In addition, we also have a parasympathetic nervous system that sort of sits in a checks-and-balances position with the sympathetic nervous system. And that's how we break this up. The somatic nervous system is just the somatic nervous system. So it has just sort of one function, and it's trying to control voluntary muscle. So the neurotransmitter that we use here, which you may recall-- and I'll put this in parentheses-- is acetylcholine. And we abbreviate that ACh for acetylcholine. What about the neurotransmitters that are used by the sympathetic and the parasympathetic nervous system? We actually sort of know them already, at least for the sympathetic nervous system. And we can come up with it. And the way you know them is if you think about what the sympathetic nervous system does. Because I'm sure you've heard of this phrase called your fight and flight response. Fight or flight. And so that's when you're in a dire situation and your body senses, uh-oh, I may die at any second now. I need to do something to get out of here. And so you activate the sympathetic nervous system so that you can achieve fight or flight. You start pumping adrenaline through your body, and you get your heart to beat faster so you can pump more oxygen to your legs to help you run quicker and get away. So that's fight or flight. And so I mentioned adrenaline, which is an endocrine hormone that's secreted to help with this. But it also has a neurotransmitter friend that does the same thing. And so the neurotransmitter friend that I'm going to write up here, it's not adrenaline, but it's noradrenaline. Starts with an N. And another term for that is norepinephrine. I'll write it out. Norepinephrine. Or noradrenaline. And so that's the neurotransmitter that's used by the sympathetic nervous system. What about the parasympathetic nervous system? Well, oddly enough it actually uses the same one that the somatic nervous system does. And the way that you can sort of differentiate this from the sympathetic nervous system is that, while the sympathetic nervous system is for the super, hardcore, intense moments where it's fight or flight, the parasympathetic nervous system is a little more chill. This is for rest and digest. So when you're going to sleep and you're trying to relax so your heart rate can lessen and your muscles and your heart aren't contracting as quickly. Or if you just ate a big meal and you need to digest that food, the parasympathetic nervous system will tell the stomach to churn that food up so you could digest it in your intestines as you also propel it along with the smooth muscle in there. So that's achieved by acetylcholine. All right? So that's the two major divisions of the central nervous system, autonomic and somatic.