 Let's look at what the endocrine system means. What are the different hormones that they produce and what their functions are? So let's start with what's an endocrine system? Well, an endocrine system is a bunch of ductless glands which are found in our body. That's what we're gonna study, what these glands are. All right, so what are these ductless glands? Let's start with the wood gland. The wood gland is any organ that secretes things. For example, something that you might be familiar with would be your sweat gland. It secretes sweat onto your skin. Your salivary gland is the one that secretes saliva into your tongue. So anything that secretes stuff is what we call as a gland. But you can see the saliva and the sweat glands, they have a piping system. They have a duct to carry their secretions to wherever they're supposed to go, right? So these glands are called duct glands. Makes sense? Now in contrast, can you guess what ductless glands are? Well, these are the glands that do not have a duct. As you can see, look at them. The colored ones, which we're gonna talk about. They don't have any ducts. So where do the secretions go? Well, they secrete things directly into the blood and it's the blood which takes those secretions to all the cells. And it's these secretions done by the ductless glands which we call as hormones because they're messenger molecules and we've talked about them in our previous video, right? And so we're gonna talk about what are the different or what are the major ductless glands which are found in our body and what are the major hormones that they secrete? And just for the sake of naming, the gland, the system of duct glands are technically called the exocrine system. So we will concentrate only on the endocrine system. All right, let's begin. Let's start from the bottom because I find them easier to remember. So if you're a male or if you're a boy, then you will have testes. These are your endocrine glands because they secrete a hormone into the blood called testosterone. Test, testosterone. I need to pronounce it right to get the spelling right. So what does the testosterone do? Well, its major job is in the development of the male sex cells, sperms. So I'm just gonna write sex cell development, okay? But they also help in your sexual maturity, like the beard and the moustache that you get, the chest hair that you get, all of that is also major lead you to the testosterone in males. On the other hand, if you're a female, then you will have ovaries. As you can see, these things. These are the ovaries. And you know what they secrete? They secrete, again, the major hormones they secrete. One is estrogen. Estrogen. You can also spell it without the O. That's also acceptable. And another major hormone that they secrete is called progesterone. Progesterone. And again, what are their major job? Well, its major job is to produce sex cells in females, that is eggs, excels, or ovum, you can say. And they're also responsible for the sexual maturity that you find in females, like, which is responsible in the widening of the hips, the enlargement of the breasts, and also changes that happen during the pregnancy. It's these hormones that regulate that. And so these are collectively called the sex hormones. And they're also responsible for the mood swings that you get sometimes. So the next gland is over here. It's called the pancreas. I always wondered, why is it called pancreas and not pancreas? It's a single organ, right? I don't know. It's just the way it is. And what is its secret, you know? Its secret is an important hormone called insulin. Insulin. And its major job is to control blood sugar. What do I mean by that? And why is this important? Let's take a situation. Imagine you eat something very delicious and also very sugary. Let's say an ice cream or a cake. The moment you eat that, because it has a lot of sugar after its digestion, the blood sugar level increases like anything. Now, the problem with that is, if there's too much blood, too much sugar in your blood, that sugar can start damaging the blood vessels. And if your blood vessels get damaged, your vital organs may not get the required blood and the oxygen, and that could be catastrophic. So we need to reduce that sugar level in your blood, right? How do we do that? Well, that's where pancreas come into picture. The pancreas will detect this high sugar in your blood and immediately start releasing insulin into the blood. What does insulin do, you know? Insulin will reach its cells and it will give them a message and say, hey, start absorbing sugar. Start absorbing sugar. So that increases the absorption of the sugar from the blood and as a result, it will now lower the levels of the sugar in the blood. Now, in some people, the pancreas may not be able to create enough insulin and so that condition is what we call diabetes. You may have heard of this. And diabetic patients are often advised not to eat food with a lot of sugar in it, right? Now, it makes sense because there's not much insulin to control that blood sugar level. And this is basically how I remember the function of insulin. I remember that diabetic patients always get an injections of insulin. That's how I remember the insulin is responsible for controlling the blood sugar. Also, a small side note on pancreas is that they can act like an exocrine gland as well. As an exocrine gland, they secrete digestive juices using the duct into the stomach. So pancreas are the only mixed glands in our body. All right, up next are these glands which are shaped like a hat sitting on top of kidneys. You can call them as kidney hat glands or more technically they are called the adrenal glands. And he guesses what hormones they secrete. Well, the major hormone they secrete is the famous one. It's called the adrenalin, adrenalin. And adrenalin is our fight or flight hormone. So let me just write that down over here. This is our fight or flight hormone. So whenever you're in a dangerous situation or you get super excited about something or you get super anxious about something, your heart starts beating and you start sweating and everything, that's basically caused by your adrenalin. We usually say there's an adrenaline rush that I'm getting. All right, up next is a gland which you can find in your neck. It's called the thyroid gland. Thyroid gland. And one of the major hormones that it produces is called thyroxine. And you know what thyroxine does? Thyroxine helps in regulating, regulating the metabolism. I'm just gonna write metabol over here. It helps in regulating the metabolism of fats, carbohydrates and proteins. So basically it helps in regulation of digestive functions. Now if the thyroid gland does not produce enough thyroxine, can you guess what's gonna happen? Well, without much thyroxine, the food that you eat will not metabolize and so you will not be able to get energy from the food. And as a result, you'll feel like eating more food, you will feel absolutely lazy and that will make you gain weight and can make you obese. And so if you know anybody who has this thyroid problem, please be sensitive to them. It's very easy for us to say, hey, go to the gym and work out and lose weight and stop eating. But it's actually a medical problem. You and I will not be able to understand that. So we need to be mindful of this. And this is also basically how I remember the functions of thyroxine. I remember that some people who are obese have the thyroid problem. Another interesting side note is that the thyroid gland is the biggest endocrine gland of our body. And why that's interesting is because pancreas is actually bigger than thyroid gland. But the thing is, like I said earlier, pancreas has two parts. One part which acts as an endocrine system. Another part which acts like an exocrine system, giving out digestive juices. So the endocrine part of the pancreas is actually very, very tiny. And that's why the thyroid gland becomes the biggest endocrine gland. Finally, this brings us to a very tiny gland found in our brain, which is called the pituitary gland. If I zoom in on you can see it a little bit like this. If you're wondering, it is not the tiniest gland of our body. There is another gland called as the pineal gland in the brain. We'll not talk about that, okay? Anyways, what does it do? Well, the pituitary gland, one of its jobs, is to release growth hormones, you know, which controls growth in your body. If a lot of growth hormones are produced, abnormally high, then the person can become abnormally tall as well. On the other hand, if abnormally less amount of growth hormones are produced, then that person can become a dwarf. But the pituitary gland also has another important job. Okay, there is a reason it is called the master gland. Any guesses why it's called that? The master gland of our body. It's called so because it's the pituitary that actually controls the secretions of all the other endocrine glands. For example, if the thyroid gland has to, you secrete thyroxine, it's the pituitary that sends the hormone to the thyroid to do that, and then the thyroid will start sending thyroxine. Similarly, it's the pituitary that will maybe send a hormone to pancreas that will trigger the pancreas to send insulin. So it's the pituitary gland that controls the secretions of all the other endocrine glands. That's why it's called the master gland. So that's pretty much it. We'll talk more about the hormonal feedback system and iodine deficiency in a future video. So to summarize, endocrine glands are glands which do not have duct. They directly secrete hormones into the bloodstream, and these are some of the major endocrine glands, and these are some of the major hormones produced by these endocrine glands.