Endocrine System | Summary

welcome to science with Susanna the purpose of this video is to give you a quick review of the endocrine system or an introduction to it if you've never heard of it so the endocrine system means inside growth and it is composed of the organs in your body that make hormones we're going to represent hormones in this video with green dots so we'll put some in this cell over here these could be the hormones that are chemical messengers that travel in the bloodstream let me use a black pen for this so hormones are chemical messengers that travel in the bloodstream so then we can take our green pen again and put some of those in this blood vessel here we can remind ourselves that it's a blood vessel by making it pink so this represents a blood vessel and the green dots represents the represent the hormones traveling then you can use a green highlighter to show that cells in your body make hormones different kinds of hormones and then those hormones are released into the bloodstream and then from there they go to target cells now I have two different pathways here because sometimes the target cells have receptors on their outside and sometimes the receptors inside the cell so the hormones will then when they reach their target they can bind to a receptor on the outside of a cell or on the inside of the cell so I used a green dot to represent that you can show the hormones coming out of the blood like this going over and what's cool about some hormones like steroid hormones they can diffuse straight through the cell membrane like that because they're nonpolar so I always like to make my receptors orange so let's color this receptor orange and this receptor orange and then let's label these this is a cell membrane receptor and this one is an intracellular receptor and both of these are what we call a target cell so a hormone can only influence a cell if it has receptors on it or inside of it steroid hormones are able to go inside to bind because they are nonpolar so steroid hormones are for example estrogen testosterone progesterone cortisol and aldosterone and also thyroxine sometimes you've heard of that is just a tirade hormone but these ones get to go inside and then the other kinds of hormones are what we call amino acid-based so they either are a protein or they're derived from a protein are there just a few amino acids so amino acid based hormones these ones are polar and or you might also have learned the word hydrophilic so because of that they don't diffuse through the membrane and they have to bind to a receptor on the outside of the cell just a one comment about sensitivity if we say that a cell is very sensitive to a hormone usually what that means is that there are many receptors on the surface so if a cell is sensitive like if it's sensitive to insulin then it will have a lot of receptors to insulin if it is resistant it will have fewer okay so then I wanted to go back over here to this cell that was originally making the hormone so these green dots are present hormone and I want to remind you something that endocrine organs are not and that is that they are not exocrine so right here let's draw a skin or mucous membrane that's what this represents so cells that make exocrine products why don't we put those in yellow so they might make something like saliva or digestive enzymes and those are secreted through a duct and onto a membrane so exocrine glands send their products down a duct which is a just a tube and that's what this represents onto a membrane and your skin is considered a membrane a cutaneous membrane or maybe the mucous membrane like your GI tract so some examples of exocrine products would be sweat tears digestive enzymes that go into the stomach and the intestine mucus these are all examples of exocrine and I want to focus on endocrine in this video but it's hard to avoid making sure that you guys know the difference here I see this so often on standardized exams where they expect students to know that exocrine glands release their products onto a membrane of some kind and that they have ducts whereas exocrine or sorry endocrine glands so hormones do not have ducts and they release their products into the bloodstream so there's a little review of that which I feel certain will come in handy for you at some point in your education knowing the difference between these and some organs can be both right like the pancreas makes all your digestive enzymes but it also makes insulin okay so now let's go ahead and look at very quickly some different kinds of hormones now I have a couple other several other videos actually that go into more detail but what I wanted to do here was give you an overview if you're studying for the Tees exam or you just want to freshen up or you just want to find some themes with hormones I really think you might find this helpful so let's go down here and I've drawn a blood vessel so here's a blood vessel and I found that you can group a lot of these according to if they make something become more plentiful in the blood or less plentiful in the blood so watch this this is kind of cool we're going to use a blue pen to name all the hormones we talked about in this blood vessel and then we'll use purple for making something more plentiful like this girl and this one who and this one just half of it and then who okay so and then some things we're going to talk about also decreasing so I don't I use blue for that okay ready to go on this so this you might recognize as a little sketch of glucose so this is representing blood sugar and when we say blood sugar we essentially always mean blood glucose because you don't really measure fructose in the blood okay so the and then let's get your blue pen the hormone that makes blood sugar go up is called Lucca gone and it comes out of the pancreas and it causes the liver to make blood sugar go up the pancreas also makes insulin and that makes blood sugar go down so glucagon makes blood sugar go up insulin makes blood sugar go down in the blood okay now let's look at calcium calcium is stored in your bones and so if you need more calcium in your blood then parathyroid hormone stimulates your bones to break down and calcium goes up in the blood so this is called parathyroid hormone this is another one that I see on standardized exams all the time they really like you to know that PTH makes your blood calcium go up and then there is another less discussed hormone called calcitonin it comes out of your thyroid gland and it makes blood calcium go down I don't see that one come up too often in the literature but I didn't want to completely skip it on this overview ok then these are red blood cells and when you make there be more red blood cells then you're going to be able to carry more oxygen the hormone that does that comes out of the kidney and it's called erythropoietin which means red formation or EPO this one's been implicated in blood doping because if people inject it they can make their red blood cells go up exceptionally high and so then this person can carry more oxygen okay so erythropoietin makes red blood cells go up in the blood because it stimulates red blood cell formation from the bone marrow okay next I'd like to talk about water you're going to make there be more water in the blood with the hormone anti diuretic hormone this hormone is made in the brain and then it is affects the kidneys and it makes the kidneys reabsorb more water so sorry so water goes up in the blood that's going to increase blood volume and can then indirectly increase blood pressure okay similarly then the next blood measurement will look at is increasing sodium in the blood and the hormone that does that is aldosterone aldosterone is a steroid hormone that comes out of the kidney and its nickname is aldo and aldosterone makes your kidneys hang on to more sodium and by doing that water follows salt and then you get more blood volume in your blood vessels and then that can indirectly raise blood pressure notice I have a downward arrow on this one too and those are hormones called Natura tech peptides and the Natura DIC peptides are released mostly from the heart itself when it's when pressures a little bit high in the heart and you see the root word nat Rio here that means salt and so these are going to make your kidneys lose salt so Natura DIC peptides make your kidneys lose salt so that blood volume goes down and aldosterone makes your kidneys hang on to salt and that makes your blood volume go up okay and then last just a grouping of some blood vessels that make blood Orser some hormones that make blood pressure go up epinephrine or adrenaline is the one people are usually most familiar with epinephrine directly makes blood vessels constrict and blood pressure go up similarly angiotensin ii makes blood pressure go up directly by constricting blood vessels angiotensin ii also stimulates more release of aldosterone and more release of antidiuretic hormone and in so doing it all it's a very potent raiser of blood pressure and then you could say that blood pressure is decreased then by Natick peptides as well so you could put this in both categories if you wanted then when I was about done with my sketch I realized oh my goodness I forgot my favorite hormone which is cortisol so cortisol a steroid hormone from the adrenal medulla makes inflammation go down cortisol is also very important increasing the availability it actually increases blood glucose and increases fat breakdown so I like to think of it as your stress hormone or mobilizing energy so to recap then cortisol makes inflammation go down during times of stress and so it inhibits the immune system and it makes blood glucose and fat breakdown go up and I have a whole video about the adrenal hormones so that you can watch if you want to know more about that ok then just a few more to talk about here a sexual maturity and reproduction are controlled by the sips of steroid hormones and pituitary gland hormones so you've got a hormone called FSH and LH and those stand for follicle stimulating hormone and luteinizing hormone and these help to regulate estrogen progesterone and testosterone in males in the testes and in so doing they control the development of sperm and of eggs and the increasing the thickening of the lining of the uterus as well as maintaining secondary sex characteristics so that reproduction can be successful so this is actually one two three four five hormones here that are all implicated in sexual maturity and reproduction then over here this is a mammary glands development milk production and release is under the control of two important hormones prolactin and they're both from the pituitary gland prolactin and then oxytocin that's stored in the pituitary gland two hormones help during pregnancy the mammary glands develop and begin producing milk and then oxytocin actually allows the milk to be released when the baby is nursing last hormone I'd like to discuss is a growth hormone and growth hormone is important for helping kids grow of course so their bones get longer their muscles get stronger but then throughout our life even once we've reached our adult size repair or I should add that here a cell repair is critical and but muscle maintenance and all of that sort of stuff is stimulated by growth hormone well there you have it just a few minutes you can find the drawing notes and practice questions at science with Susanna comm and also in this playlist for the endocrine system you can find in on my website you can find other videos on the endocrine system that go into a little more detail on virtually all of these hormones

Channel: susannaheinze

Views: 127,811

Keywords: endocrine system, steroid hormones, amino-acid based hormones, exocrine glands, major hormones, insulin, glucagon, cortisol, aldosterone, prolactin, oxytocin, angiotensin II, epinephrine, natriuretic peptide, FSH, LH, estrogen, progesterone, testosterone, growth hormones

Id: 6gadsqrNJ3Y

Length: 16min 42sec (1002 seconds)

Published: Thu Apr 04 2019