1 00:00:10,919 --> 00:00:15,119 Hey everyone, and welcome back to part 3 of our 4-part video series on nutrition. 2 00:00:16,460 --> 00:00:21,480 Last time, we talked about the respiratory system and how oxygen and carbon dioxide travel 3 00:00:21,480 --> 00:00:23,460 through our bodies and get used by our muscles. 4 00:00:24,500 --> 00:00:28,120 Today, we're going to be connecting what we learned from the respiratory system to the 5 00:00:28,120 --> 00:00:29,059 circulatory system. 6 00:00:29,480 --> 00:00:33,380 So far, we've learned about how our respiratory system brings in oxygen and the end result 7 00:00:33,380 --> 00:00:37,640 of oxygen entering our bloodstream, but how exactly does the oxygen get to where it needs 8 00:00:37,640 --> 00:00:38,000 to go? 9 00:00:38,340 --> 00:00:40,679 That's where the circulatory system comes into play. 10 00:00:41,399 --> 00:00:49,500 The circulatory system takes the nutrients we eat and air we breathe and delivers all the essential nutrients to our organs, bones, brain, and muscles to help them keep working. 11 00:00:51,020 --> 00:00:52,820 Okay, I want everyone to try something. 12 00:00:53,219 --> 00:00:58,679 Take your pointer and middle finger and press them to the side of your neck just underneath your jaw and beside your windpipe. 13 00:00:59,340 --> 00:01:00,240 Can you feel your heartbeat? 14 00:01:01,020 --> 00:01:03,280 Move your fingers around and see if you can feel where it's strongest. 15 00:01:04,599 --> 00:01:06,719 Congratulations, you just checked your heart rate. 16 00:01:06,719 --> 00:01:10,840 The thumping under your fingers that you felt is your heartbeat. 17 00:01:11,319 --> 00:01:14,760 We talked earlier about how the lungs bring oxygen to our blood through the alveoli. 18 00:01:15,340 --> 00:01:19,099 The red blood cells absorb the oxygen from the lungs and get pumped back into the heart, 19 00:01:19,400 --> 00:01:22,459 and the heart then pumps it all over the body to keep it operational. 20 00:01:23,159 --> 00:01:26,319 But let's dive in and learn a little bit more about the circulatory system. 21 00:01:27,579 --> 00:01:29,780 The heart is an organ that acts like a pump. 22 00:01:29,980 --> 00:01:33,739 The heart is separated into two sides by the septum, which acts like a wall. 23 00:01:34,400 --> 00:01:37,159 Each side has two chambers, one above and one below. 24 00:01:37,819 --> 00:01:41,980 The chambers that are above are called the atria, and the two lower chambers are called ventricles. 25 00:01:42,500 --> 00:01:48,379 So essentially, the heart has four main rooms, the right atrium, the right ventricle, the left atrium, and the left ventricle. 26 00:01:48,920 --> 00:01:51,579 When the ventricles contract, they push the blood out of the heart. 27 00:01:52,099 --> 00:01:55,359 When you place your hand on your chest and feel a thump, that's your ventricle's heart at work. 28 00:01:56,420 --> 00:01:58,920 Blood is super important to the circulatory system. 29 00:01:59,000 --> 00:02:01,819 Blood contains liquid plasma and three types of cells. 30 00:02:02,500 --> 00:02:05,859 Red blood cells absorb oxygen from the lungs and transport it through the body. 31 00:02:06,620 --> 00:02:09,960 Platelets are the band-aids of the body and help stop bleeding whenever you get cut. 32 00:02:10,400 --> 00:02:14,120 Without platelets, we wouldn't get scabs, but we also wouldn't stop bleeding if we got hurt. 33 00:02:14,979 --> 00:02:19,560 White blood cells are the soldiers of the bloodstream because they fight germs and infections that enter the body. 34 00:02:20,139 --> 00:02:24,599 Whenever you get sick, the white blood cells come to the rescue and attack the infected cells in your body. 35 00:02:25,560 --> 00:02:29,699 Blood gets carried around by blood vessels, and these vessels come in three different types. 36 00:02:29,699 --> 00:02:35,840 arteries, veins, and capillaries. Arteries carry blood away from the heart. Veins carry blood back 37 00:02:35,840 --> 00:02:40,979 to the heart. And capillaries are super tiny blood vessels that connect the smallest arteries to the 38 00:02:40,979 --> 00:02:46,379 smallest veins. Capillaries also have very thin walls, so nutrients, gases, and waste products 39 00:02:46,379 --> 00:02:51,900 can go through them and into the cells of our bodies. So how does blood get pumped around our 40 00:02:51,900 --> 00:02:56,759 body? Well, first, deoxygenated blood enters through the right atrium and then into the right 41 00:02:56,759 --> 00:03:01,539 ventricle. The right ventricle pumps blood through the pulmonary artery to the lungs where it gets 42 00:03:01,539 --> 00:03:07,139 oxygen. From there, the blood drops off its carbon dioxide so it can carry its oxygen to the 43 00:03:07,139 --> 00:03:12,520 pulmonary veins of the heart. The oxygenated blood then goes into the left atrium and then the left 44 00:03:12,520 --> 00:03:18,560 ventricle. The left ventricle pumps the blood throughout the aorta, or the top of the heart, 45 00:03:18,560 --> 00:03:23,379 which channels it to the rest of the body. Once the blood drops off the oxygen and nutrients where 46 00:03:23,379 --> 00:03:28,120 needed, it picks up any carbon dioxide and waste products the muscles and tissues have excreted 47 00:03:28,120 --> 00:03:31,219 and carries it back to the superior and inferior vena cava. 48 00:03:31,819 --> 00:03:35,659 The superior and inferior vena cava are attached to the right side of the heart, 49 00:03:35,879 --> 00:03:37,419 which is where we began our journey. 50 00:03:37,919 --> 00:03:39,120 Wow, we made it full circle. 51 00:03:40,520 --> 00:03:44,460 Okay, so we connected a lot of dots today, so let's take a second to recap. 52 00:03:46,639 --> 00:03:50,039 We learned about how the body needs nutrients and oxygen to survive 53 00:03:50,039 --> 00:03:54,280 and how exactly the respiratory and circulatory system work together to do just that. 54 00:03:54,860 --> 00:03:58,039 We also learned how to check our pulse to feel our hearts hard at work. 55 00:03:59,500 --> 00:04:04,680 We then learned how blood takes oxygen and drops off carbon dioxide and carries it to the heart 56 00:04:04,680 --> 00:04:09,060 through the use of veins. Arteries then take blood away from the heart into the rest of the body, 57 00:04:09,240 --> 00:04:14,280 which get nutrients and oxygen from three different types of blood cells. After trading nutrients for 58 00:04:14,280 --> 00:04:18,620 carbon dioxide, the blood then comes back to the heart so it can be pumped into the lungs and start 59 00:04:18,620 --> 00:04:24,620 all over again. And to think, this all happens in a heartbeat. Well everyone, I think we covered it. 60 00:04:24,860 --> 00:04:28,819 Thank you for adventuring with me today as we connected the respiratory system to the circulatory 61 00:04:28,819 --> 00:04:33,500 system. I hope you learned a lot, and stay tuned for the last, but certainly not least, 62 00:04:33,660 --> 00:04:35,199 part four of this nutrition series.