 You've probably heard about hormones, right? But what are they and how do they work? Well, let's find out So what are these hormones? You can think of hormones as messenger molecules So hormones are messenger molecules And what do they do? well, they bring They bring about control and coordination control and Coordination in your body Now when you listen to this a couple of questions that might come to your mind One is you may have already you may have already studied that the nervous system is the one that produces control and coordination in your body, right? So why do we need another system to do the same thing? Well, let me tell you that right now immediately Nervous system is great But the problem with that the drawback of that is that it only affects a limited number of cells Your nerves are only connected to very limited number of cells in your body So not all cells can be controlled by your nervous system hormones on the other hand they can affect all The cells potentially so they can reach all the cells and that's the beauty of hormones So that's the main reason why we have the hormonal system. Let me just write that down The main advantage of hormones over our hormonal system over the nervous system is that these hormones these Messenger molecules you can call them as signaling molecules. Also, whatever you want, but they can reach all cells Okay, but you may be wondering well, how does it work and what exactly do you mean by hormones bring about control and coordination, right? Well, let's take a very specific example. Let's work with an example Imagine you are walking on the street, you know casually surfing your mobile phone and suddenly a Lizard jumps on you now your eyes are able to spot that lizard and Immediately the signals from your eyes and maybe from your ears They go to your brain and your brain triggers and a reflex action This is your nervous system by the way triggers a reflex action which because of which you immediately bend down and you dodge that lizard Great your nervous system helped you avoid that danger, but the danger is not over yet That lizard is still there. It can attack you at any moment So your body needs to prepare for this danger What prepares your body for this where your nervous system can't do it because to prepare your body a lot of Cells will be involved and like I said before the nervous system cannot reach all the cells So it's your hormones that can help you in preparing the your body for this situation So in this very specific situation the small triangle shaped organs Which are present on top of your kidney they get triggered by the nervous system and as a result they Start producing a particular kind of hormones. You may have heard of these hormones. They are called adrenaline Now the name is not very important We'll talk about the different kinds of hormones and who produces who secretes them and what are their functions in a separate video All together, but let's just think about what happens like how these hormones system work So these things will start releasing these Hormones basically messenger molecules and they release them directly into the blood vessels. That's important All right, they release them into the blood vessels So the hormones these messenger molecules find find their way into the blood vessels They go to the heart and eventually the heart Circulates that blood to all the parts of your body all the cells of your body and that's how this Hormone this adrenaline hormone Reaches all the cells of your body Okay What happens next all the cells have gotten the message what happens next? Well, not all cells will respond to that message. That's the second thing to understand about hormones You see in order to respond to a hormone the cells need something very special called a receptor Let me just write that down So only those hormone will respond only those are you holding only those cells will respond cells which have something called a receptor Think of a receptor as a key to unlock the message So only those cells which have the receptors for their hormone can unlock the message and start responding to it So in our example the cells in your heart for example have the receptors for adrenaline And as a result, you know how they will respond to this hormone that those cells will make your heart beat faster As a result the blood starts getting circulated faster. That's great Secondly the cells in your lungs they also have the receptor So they start responding to this by taking in more oxygen providing more oxygen to your cells That's awesome, right? That's what you need. What else happens? Well, it turns out that it's the same hormones that will start redirecting the blood Away from your digestive system away from your skin because in this situation Blood is not needed much over there But it redirects it to the important parts of your body like your skeletal muscles in your arms and your legs because they will Be involved in this situation heavily Another thing that these hormones will do is they will lower down lower down your pain sensitivity So you can bear more pain and Now as a result of all of this Can you see that your body has now been prepared to either fight that lizard or use your legs and get the hell out of there That's probably what I will do So this is just one example of how hormones can bring about control and coordination in your body. It's pretty awesome, right? I like to think of these organs that secrete hormones as a TV broadcasting station Like say Tata sky it sends signals to all the TVs Similarly, this this organ sends hormones to all the cells But do all the TVs respond to that message? No Only those TVs can respond which have a Tata sky dish, right? Similarly over here only those cells can respond which have a particular receptor for that particular hormone And so you see the beauty of this is that such hormone secreting organs can be located in one part of the body And they can easily control other parts of the body, which is located in some other corner It's amazing, right? And it's because of this hormones have a huge role in our life and in our bodies Not only responding to stressful situations, but they also help in growth. They are responsible in growing our height They're responsible in our sexual maturity, but also subtle things like they're responsible for Maintaining the blood sugar blood sugar level in our blood vessels stuff like that and we'll talk more about, you know Functions of various hormones and all of that in another video altogether But anyways before we wind up, let's see if we can differentiate between the hormonal system and The nervous system. In fact, can you pause the video and just think about this? What difference is can you make out between the nervous system and the hormonal system? Go ahead pause the video and think about this Alright, let's see. I think the first difference is something that we kept talking about That is the nervous system has a very limited reach It can only reach few cells in your body limited number of cells in our body But the hormonal system the technical term for this is called the endocrine system Okay, but again, don't worry too much about that We'll talk more about that in future videos as of now. Just call it as hormonal system The beauty of this system is that the hormones the signals can reach all the cells and why is that? Why does this have limited reach? It has limited reach because the nervous system uses the nerve tissues right a dedicated network to send Messages and these nerves can only connect to a few cells in our body Right, that's why it has a limited reach on the other hand the hormonal system What how does how do the hormones reach different cells? Well, they basically use the blood tissue they use the blood and blood can't reach all the cells That's why in the hormonal system the hormones can reach all the cells Okay, but this also means that the nervous system is extremely fast because it has a dedicated network. It has a very it's like an express highway, right? It has a System of nerves just for sending the signals But the hormonal system on the other hand is very slow. It doesn't have a dedicated Network it just uses the blood So the message the harm the mess the molecules have to go into the blood Then the blood has to go to the heart and the heart pumps it to all the parts of the body So it's a plate. It's pretty slow compared to the nervous system And of course another important difference you can you might have noticed is the nervous system uses electrical signals Majorityly at least it's the electricity right on the other hand. What about the hormonal system? We're using molecules basically chemical Right, so these are some of the major differences that we can find between the nervous system and the hormonal system Two systems which work together to bring control and coordination in your body