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Endocrine system (major hormones & functions)

Let's explore the major endocrine glands, their major hormones, their major functions. Created by Mahesh Shenoy.

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Video transcript

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 we are which are found in our body that's what we're gonna study what these glands are alright so what are these Occulus glands let's start with the word gland the word 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 us onto your skin your saliva gland is the one that secrete 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 alright so these glands are called dark glands make 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 going to talk about they don't have any ducts so where do these accretions go well they secrete things directly into the blood and it's the blood and that 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 talked more talked about them in a 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 one of 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 alright 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 tests toss Terron I need to pronounce it right to get the spelling right so what is this what what do what does the testosterone do well it's major job is in the development of the male sex cells sperms somebody's 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 majorly due 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 Auris you know what basically it they secrete again the major hormones they secrete one is estrogen estrogen you can you can also spell it without the Oh that's also acceptable and another major hormone that they secrete is called progesterone Pro yes Terron and again or at 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 all right 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 pankley yeah it's a single organ right I don't know it's just the way it is and what is it sacred you know it secretes an important hormone called insulin insulin and it's 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 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 wizards 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 the diabetic patients always get in injections of insulin that's how I remember the initial insulin is responsible for controlling the blood sugar also a small side note on pancreas is that they can act like an egg so cream 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 had glands or more technically they are called the adrenal glands adrenal glands and he guesses what hormones they secrete well the major hormone they secrete is the famous one it's called the adrenal in adrenal in and adrenaline is our fight or flight hormone so let me just say that down over here this is our fight or flight hormone so whenever you are 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 adrenaline 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 you know what ty Roxon does thyroxine helps in regulating regulating the metabolism I'm just gonna write metaball 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 and it guess what's gonna happen but without much thyroxine though 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 feel like eating more food you feel absolutely lazy and that will make you gain weight and can make you obese and so if you know anybody who has this title 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 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 connect 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 like I said earlier pancreas has two parts one part which acts as an endocrine system another part which acts like an exocrine system you know giving out digestion users so the endocrine part of the pancreas is actually very very tiny and that's why the thyroid gland becomes the biggest and dokin gland finally this brings us to a very tiny gland found in our brain which is called the pituitary gland if i zoom in here 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 will not talk about that okay anyways what does it do well the pituitary gland one of his 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 be secretary oxen it's the pituitary that sends a hormone to the thyroid to do that and then the thyroid will start sending thyroxine similarly it's a pituitary that will maybe send 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 and Glantz