1 00:00:00,000 --> 00:00:08,960 Hello everyone, today we're going to study the endocrine system and you know this is like one 2 00:00:08,960 --> 00:00:15,060 of the two main parts we are studying in this unit, okay? So we have started with the nervous 3 00:00:15,060 --> 00:00:24,719 system and we have explained how it coordinates the functioning of our body and the endocrine 4 00:00:24,719 --> 00:00:32,240 system does the same so it coordinates actions in our body but it does it in a different way 5 00:00:32,240 --> 00:00:41,979 okay and we will study today how it how this happens okay so first of all hormones are 6 00:00:41,979 --> 00:00:48,740 produced in our body in many places they are called endocrine glands and those endocrine 7 00:00:48,740 --> 00:00:56,380 glands they have special cells which are capable of producing a hormone okay soon in a moment i 8 00:00:56,380 --> 00:01:03,979 will explain you which endocrine glands do we have but first of all i want to explain you the mechanism 9 00:01:03,979 --> 00:01:12,620 how these endocrine glands produce hormones okay first of all so we have here let me use 10 00:01:12,620 --> 00:01:20,560 a highlight that i have here okay so um the endocrine system as i said is made of 11 00:01:20,560 --> 00:01:26,599 many endocrine glands okay you have it here and when they have to produce a hormone 12 00:01:26,599 --> 00:01:34,599 these hormones are released into the bloodstream so in our blood in our circulatory system 13 00:01:34,599 --> 00:01:41,340 okay so here in this example you have these these ones here are supposed to be cells from 14 00:01:41,340 --> 00:01:48,540 the endocrine system they are producing hormones which are supposed to be these yellow balls here 15 00:01:48,540 --> 00:01:55,400 and when they produce a hormone what they do with it is to put it in a blood vessel vessel okay so 16 00:01:55,400 --> 00:02:03,799 they go along with our blood they travel all the time around our body okay so they move with the 17 00:02:03,799 --> 00:02:12,319 bloodstream. Good. Hormones, they are like a message, okay? So they are like a message that 18 00:02:12,319 --> 00:02:20,400 moves in our blood and has to reach certain cells. And the cells that are going to receive the 19 00:02:20,400 --> 00:02:27,840 hormone are called target cells. You have it here, okay? So target cells are specific cells that will 20 00:02:27,840 --> 00:02:34,979 receive the hormone soon I will put some examples but here in this drawing you 21 00:02:34,979 --> 00:02:40,960 can see these target cells they are going to receive the message which is 22 00:02:40,960 --> 00:02:50,099 the hormone okay a target cell is a target cell if if it's capable or if it 23 00:02:50,099 --> 00:02:57,219 can receive the specific hormone so in order to receive the hormone it needs to 24 00:02:57,219 --> 00:03:05,500 have a receptor okay so as you can see here this target cell it has this y 25 00:03:05,500 --> 00:03:12,699 shaped thing in the membrane this is the receptor and the receptor can feel or 26 00:03:12,699 --> 00:03:20,139 detect the hormone okay so as we can see here a target cell has a receptor that 27 00:03:20,139 --> 00:03:26,099 can only bind with a specific hormone okay and this message is transmitted 28 00:03:26,099 --> 00:03:33,340 provoking a response from that target cell good I told you in the beginning 29 00:03:33,340 --> 00:03:38,439 that the endocrine system works along with the nervous system but they are 30 00:03:38,439 --> 00:03:44,479 different okay so in this table here you have the main differences between them 31 00:03:44,479 --> 00:03:52,479 the nervous system works through nerves right we have studied that and the 32 00:03:52,479 --> 00:03:58,639 endocrine system i just said it works through the blood right so it releases hormones to the blood 33 00:03:58,639 --> 00:04:06,719 the nervous system uses nerve impulses as we said before in the previous days whereas the 34 00:04:06,719 --> 00:04:14,800 endocrine system uses hormones okay and the nervous system was very quick we said that many 35 00:04:14,800 --> 00:04:22,240 times in the past few days it is really quick and but its action doesn't last very long so 36 00:04:22,240 --> 00:04:31,759 we have an action from the nervous system and it's immediate it's rapid but then it stops okay 37 00:04:31,759 --> 00:04:38,759 so for example if my nervous system makes move my hand because i'm getting burned 38 00:04:38,759 --> 00:04:47,220 i do it very quickly but then the action is finished okay the endocrine system on the other 39 00:04:47,220 --> 00:04:55,300 hand is slow and long term what does this mean we're going to put a hormone in our bloodstream 40 00:04:55,300 --> 00:05:04,019 and that hormone is going to be there for quite a while okay so its effect will last for a longer 41 00:05:04,019 --> 00:05:11,620 time so sometimes we have similar effects from the nervous system and the endocrine system 42 00:05:11,620 --> 00:05:19,319 but the endocrine system will be working for a longer time, okay? 43 00:05:19,899 --> 00:05:22,920 So its response is longer. 44 00:05:24,439 --> 00:05:25,120 Okay, good. 45 00:05:26,959 --> 00:05:31,779 So to introduce the endocrine system, I think this is enough, okay? 46 00:05:32,120 --> 00:05:37,120 So now I'm going to move on to the next page, if I can. 47 00:05:38,459 --> 00:05:40,000 Let me just close here. 48 00:05:43,829 --> 00:05:44,610 Can I move this? 49 00:05:44,790 --> 00:06:00,379 Yes, good and now I'm going to tell you which are the main endocrine glands. 50 00:06:00,379 --> 00:06:06,860 You have them here in the middle in your book but the image is not great so I found another 51 00:06:06,860 --> 00:06:16,259 one bigger so that I can show this to you a bit better. 52 00:06:16,259 --> 00:06:21,720 So I said we have different endocrine glands and they are distributed in different parts 53 00:06:21,720 --> 00:06:30,139 of our body okay so to begin with we have two inside the brain the hypothalamus and another 54 00:06:30,139 --> 00:06:36,939 one connected to the hypothalamus which is called the pituitary gland these two glands are going to 55 00:06:36,939 --> 00:06:43,740 receive orders straight straight from the brain okay so the brain gives order to these glands 56 00:06:43,740 --> 00:06:51,540 and they will produce those hormones okay we have another gland here in the neck next to the trachea 57 00:06:51,540 --> 00:06:59,180 and it is called the thyroid okay thyroid tiroides in spanish i'm sure you heard about it 58 00:06:59,180 --> 00:07:07,339 then on top of the kidneys we see we have seen this before when we studied the urinary system 59 00:07:07,339 --> 00:07:15,240 we have two glands one on top of each kidney and they are called the adrenal glands here it says 60 00:07:15,240 --> 00:07:22,439 adrenal cortex but cortex is the outside part only okay so it is better to say adrenal gland 61 00:07:22,439 --> 00:07:32,730 I think you have it right in your book though let me see yes adrenal glands okay and then we have 62 00:07:32,730 --> 00:07:39,670 the pancreas the pancreas we have studied the pancreas in digestion but it also produces 63 00:07:39,670 --> 00:07:45,970 hormones okay so I will explain this to you in a moment and then we have two 64 00:07:45,970 --> 00:07:54,069 more types of endocrine glands in females and we are talking in females 65 00:07:54,069 --> 00:07:59,949 about the ovaries and in males we are talking about the testicles okay and 66 00:07:59,949 --> 00:08:05,790 they are both located in the gonads okay so ovaries and testicles are endocrine 67 00:08:05,790 --> 00:08:14,910 glands too okay this is the same you have here okay but it's just the drawing is not so good 68 00:08:16,269 --> 00:08:23,389 okay good so now i'm going to go a bit deeper into the functioning of some of the hormones 69 00:08:23,389 --> 00:08:30,110 not all of them i will point you which ones are we going to study and to begin this section 70 00:08:30,110 --> 00:08:37,590 I'm going to the brain to the hypothalamus and the pituitary gland these two okay the ones that 71 00:08:37,590 --> 00:08:43,789 are located in the brain and why are they so important well first of all there are many 72 00:08:43,789 --> 00:08:49,750 hormones produced in here and some of them will affect the production of a second hormone 73 00:08:49,750 --> 00:09:02,159 so i'm going to put them together trying to make this easier for you and i'm going to select some 74 00:09:02,159 --> 00:09:09,720 of them most of them but not all of them okay so i have them here in this in this board 75 00:09:09,720 --> 00:09:17,899 so talking about hormones produced in the brain so both in the hypothalamus and the pituitary gland 76 00:09:17,899 --> 00:09:26,480 we have some of them which are going to be produced and they will have a function in a 77 00:09:26,480 --> 00:09:34,059 tissue or an organ of the body. And we have four hormones here, okay? The first one is called 78 00:09:34,059 --> 00:09:42,059 antidiuretic hormone or ADH. The second one is called oxytocin. The third one is called 79 00:09:42,059 --> 00:09:50,480 growth hormone, and the fourth one is called prolactin, okay? So these four hormones are going 80 00:09:50,480 --> 00:09:58,440 to be released in these glands of our brain, and they are going to have an action on another part 81 00:09:58,440 --> 00:10:04,879 of our body. So, sorry, not here. Okay, so for example, let's begin with the first one, 82 00:10:04,879 --> 00:10:12,720 the antidiuretic hormone. This hormone is the one that makes us not to produce too much urine. 83 00:10:13,279 --> 00:10:20,179 Do you remember when we were studying urine production? I told you. Our body can regulate 84 00:10:20,179 --> 00:10:28,220 how much urine do we produce. It depends on how much water we have drunk or it depends also on 85 00:10:28,220 --> 00:10:34,259 how hot is the weather okay so our body controls how much urine we produce 86 00:10:34,259 --> 00:10:43,779 and to control this we use this hormone the adh hormone then we have oxytocin oxytocin makes a few 87 00:10:43,779 --> 00:10:52,779 things uh one of them is to simulate contractions in the uterus it makes this both when a woman is 88 00:10:52,779 --> 00:10:58,299 giving birth, a baby, so those contractions, las contracciones del parto, okay, contractions 89 00:10:58,299 --> 00:11:07,279 when a woman is in labor, in labor, es de parto, de parto, and oxytocin is also called 90 00:11:07,279 --> 00:11:14,940 the hormone of love, okay, we produce lots of oxytocin when we love someone, and not 91 00:11:14,940 --> 00:11:24,039 only like our partner someone we love but also we produce oxytocin uh for every kind of love okay 92 00:11:24,039 --> 00:11:30,799 for our children or you know for our parents so it is it is involved in all the love responses 93 00:11:30,799 --> 00:11:40,659 which is very interesting okay so um it also makes the uterus contract when a woman is menstruating 94 00:11:40,659 --> 00:11:45,480 cuando una mujer tiene la regla o está menstruando y le duele la tripa también hay oxitocina ahí 95 00:11:45,480 --> 00:11:53,559 funcionando okay so oxytocin makes all these three things contractions during labor when we are 96 00:11:53,559 --> 00:12:02,960 menstruating the women and also i said it's a hormone related to uh to love okay so the feeling 97 00:12:02,960 --> 00:12:10,240 of love to for other people good then we talked about growth hormone growth hormone makes our 98 00:12:10,240 --> 00:12:17,899 body grow obviously and also our tissues to proliferate our cells to grow and to be bigger 99 00:12:17,899 --> 00:12:26,480 and to divide so it makes us grow in many ways and i think in the list i included also yes 100 00:12:26,480 --> 00:12:35,240 prolactin okay so prolactin is here here so prolactin can promote breast development 101 00:12:35,240 --> 00:12:45,019 when we are teenagers right in women mostly obviously and they also stimulate milk production 102 00:12:45,019 --> 00:12:52,460 in the breasts but only if we have had a baby okay so women do not produce milk 103 00:12:52,460 --> 00:13:00,740 if they haven't had a baby recently okay and i think that's all for the hormones that act 104 00:13:00,740 --> 00:13:09,720 okay which have a direct action on tissues okay so let me remind antidiuretic hormones it works 105 00:13:09,720 --> 00:13:16,960 straight away on the kidneys and on the nephrons and it makes the nephrons to not produce a lot 106 00:13:16,960 --> 00:13:24,220 of urine okay so it stops a little bit urine production then we have oxytocin oxytocin works 107 00:13:24,220 --> 00:13:31,980 in many places in our body and we've talked about contractions in the uterus and the 108 00:13:31,980 --> 00:13:39,100 love feelings growth hormone also acts in many places in our body probably making cells proliferate 109 00:13:39,100 --> 00:13:48,080 and grow and then prolactin would only work in women and specifically when we have had a baby 110 00:13:48,080 --> 00:13:57,519 okay so that our breasts can can produce milk for the baby good so and then we're going to move 111 00:13:57,519 --> 00:14:04,860 into other hormones produced in the brain this second group and this group is going to act in 112 00:14:04,860 --> 00:14:09,799 another tissue but they will make that tissue to produce more hormones i'll explain that 113 00:14:10,779 --> 00:14:15,500 First of all, which ones are we going to study? 114 00:14:16,419 --> 00:14:19,159 We have this first one, TSH. 115 00:14:19,879 --> 00:14:24,919 It makes another gland, the thyroid, to produce hormones. 116 00:14:24,919 --> 00:14:35,559 So when the thyroid receives TSH hormone, then it will produce other hormones called T3 and T4. 117 00:14:35,559 --> 00:14:44,399 second group fsh and lh this group of hormones they simulate ovaries and testicles 118 00:14:44,399 --> 00:14:51,559 and they are going to make in the testicles and ovaries they are going to make them produce other 119 00:14:51,559 --> 00:15:01,460 hormones which ones okay testicles mostly produce testosterone and ovaries produce estrogens 120 00:15:01,460 --> 00:15:08,139 and progesterone in different moments okay so yeah these are the main products 121 00:15:08,139 --> 00:15:16,320 and these second hormones testosterone estrogens and progesterone they have another function 122 00:15:16,320 --> 00:15:25,559 themselves okay so if we sorry if we go here and we go to the ovaries we can see that 123 00:15:25,559 --> 00:15:32,840 estrogens and progesterone they control the menstrual menstrual cycle and also the development 124 00:15:32,840 --> 00:15:39,799 of secondary sexual characteristics which are characteristics that makes us look like a woman 125 00:15:39,799 --> 00:15:48,980 in many ways okay and in the testicles we have testosterone and testosterone mostly makes the 126 00:15:48,980 --> 00:15:57,080 testicles to produce the espermatozoa okay and it also makes or promotes the 127 00:15:57,080 --> 00:16:01,220 development of secondary sexual characteristics okay characteristics 128 00:16:01,220 --> 00:16:06,320 typical of men we can discuss these characteristics maybe next time when we 129 00:16:06,320 --> 00:16:14,299 are together in class okay what we are talking about nice then we have let me 130 00:16:14,299 --> 00:16:22,460 see yeah and the last one produced in the brain but with action in another tissue that will produce 131 00:16:22,460 --> 00:16:32,019 more hormones is ACTH okay so ACTH you have it here it's a hormone that stimulates the adrenal 132 00:16:32,019 --> 00:16:42,039 glands the adrenal glands are here on top of the kidneys okay good so the adrenal glands you have 133 00:16:42,039 --> 00:16:48,899 them here the explanation of the hormones it produces so the adrenal glands produce cortisol 134 00:16:48,899 --> 00:16:57,440 and adrenaline the these two hormones both of them they are involved in stress responses okay 135 00:16:57,440 --> 00:17:03,919 this is something i have already told you okay so cortisol and adrenaline are produced 136 00:17:03,919 --> 00:17:12,019 as a response to stress if you remember i mentioned adrenaline already when i was explaining to you 137 00:17:12,019 --> 00:17:20,460 the nervous system and this is because adrenaline can work both as a neurotransmitter and as a 138 00:17:20,460 --> 00:17:28,859 hormone okay so it has this it has this double effect okay cortisol is just a hormone so i mean 139 00:17:28,859 --> 00:17:35,480 like it's not a neurotransmitter and it lasts a longer time okay so adrenaline 140 00:17:35,480 --> 00:17:44,279 uh lasts a shorter time and cortisol stays longer okay so when a person is very much stressed 141 00:17:44,279 --> 00:17:51,119 maybe that person can accumulate a lot of cortisol and then maybe that person can have 142 00:17:51,119 --> 00:17:58,440 trouble and problems with for example with sleeping because cortisol is very high and 143 00:17:58,440 --> 00:18:05,319 it's keeping you awake okay it doesn't let you relax so cortisol it's actually a bit dangerous 144 00:18:05,319 --> 00:18:10,900 to have lots of cortisol in our body all the time because that means we are stressed when we are not 145 00:18:10,900 --> 00:18:20,740 supposed to okay good okay so uh we are just missing one that i want you to take note of 146 00:18:20,740 --> 00:18:29,559 and this is the pancreas and you can uh now notice that the pancreas is not 147 00:18:29,559 --> 00:18:38,440 influenced by the brain okay so it's the only gland that i'm mentioning that is not controlled 148 00:18:38,440 --> 00:18:46,960 by the brain and pancreas makes two hormones the one i want to mention to you is insulin and 149 00:18:46,960 --> 00:18:56,640 insulin um takes away glucose from our blood and it put it it puts it in our cells so so when we 150 00:18:56,640 --> 00:19:05,700 have just eaten if we ate for example bread or a big big bunch of pasta or rice and then in 151 00:19:05,700 --> 00:19:13,420 digestion we have produced lots of glucose okay if we have a high glucose in our blood then insulin 152 00:19:13,420 --> 00:19:21,180 is going to work taking away this glucose and put it in putting it in our cells and for example 153 00:19:21,180 --> 00:19:26,880 this works also very much for the brain so that the brain can take up uh lots of lots of this 154 00:19:26,880 --> 00:19:37,140 glucose that it needs okay so insulin lowers blood glucose levels it keeps it down and well 155 00:19:37,140 --> 00:19:45,119 that's all it's i know it's a lot but now i'm going to ask you uh for the rest of the class 156 00:19:45,119 --> 00:19:52,039 to make a scheme okay it is important that you make something with all this information 157 00:19:52,039 --> 00:20:01,940 so what you can do now is to to make a scheme as i just said and you can make a scheme similar to 158 00:20:01,940 --> 00:20:09,000 the one i made okay similar to this one but maybe you can complete here with the function of every 159 00:20:09,000 --> 00:20:15,359 hormone okay so it is important that you know the function of each hormone and if 160 00:20:15,359 --> 00:20:21,599 it's producing the brain or in another tissue okay okay see you next day and 161 00:20:21,599 --> 00:20:27,779 you can watch this video again at home if you need it and you can ask me your 162 00:20:27,779 --> 00:20:33,000 questions and next week okay see you